Instructions for Form CT-1 X (Rev. April 2025) — Adjusted Employer's Annual Railroad Retirement Tax Return
Summary
Instructions for Form CT-1 X, Adjusted Employer's Annual Railroad Retirement Tax Return or Claim for Refund (Rev. April 2025), from the Department of the Treasury, Internal Revenue Service, dated Mar 17, 2025. The What's New section states that the period of limitations for correcting qualified compensation paid in 2020 for the employee retention credit generally expired for most employers on February 29, 2024, and for 2021 compensation on February 28, 2025, so that certain lines are now reserved for future use. It states that the COVID-19 related credit for qualified sick and family leave compensation is limited to leave taken after March 31, 2020, and before October 1, 2021, and that overreported taxes may generally be corrected within 3 years of filing or 2 years of payment, whichever is later.
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“Instructions for Form CT-1 X (Rev. April 2025) — Adjusted Employer's Annual Railroad Retirement Tax Return.”
Original at www.irs.gov. Archived at Pandemic Darlings, https://pandemicdarlings.com/source-documents/internal-revenue-service-form-ct-1x-instructions-march-2023-revisions-9242b4eb73/
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Instructions for Form CT-1 X
(Rev. April 2025)
Adjusted Employer's Annual Railroad Retirement Tax Return or Claim for Refund
Section references are to the Internal Revenue Code employee retention credit and qualified health plan
unless otherwise noted. expenses allocable to that compensation on a Form CT-1
filed for 2020 and 2021. The period of limitations for
Future Developments making corrections to qualified compensation paid in 2020
For the latest information about developments related to for the employee retention credit and qualified health plan
Form CT-1 X and its instructions, such as legislation expenses allocable to that compensation generally
enacted after they were published, go to IRS.gov/CT1X. expired for most employers on February 29, 2024. The
period of limitations for making corrections to qualified
Before you proceed with these instructions and
compensation paid in 2021 for the employee retention
TIP completing Form CT-1 X, you'll need a copy of the credit and qualified health plan expenses allocable to that
Instructions for Form CT-1 because these
compensation generally expired for most employers on
instructions don't repeat all of the information included in
February 28, 2025. Lines 39 and 40 were used only if your
the Instructions for Form CT-1. For example, these
business was a recovery startup business in the third or
instructions don't discuss who is eligible to claim the credit
fourth quarter of 2021. These instructions no longer
for qualified sick and family leave compensation or the
discuss these lines. If you think that the period of
COBRA premium assistance credit. The current
limitations is still open for correcting your 2020 or 2021
Instructions for Form CT-1 are available at IRS.gov/CT1. If
Form CT-1, you can still file the March 2024 revision of
you need a prior revision of the Instructions for Form CT-1,
Form CT-1 X to use lines 20a, 25a, 31, 32, 39, and 40.
select the link for "All Form CT-1 revisions" under "Other
items you may find useful." Reminders
What’s New If a line on Form CT-1 X doesn’t apply to you,
! leave it blank. If you’re correcting a year before
Period of limitations to make certain corrections ex- CAUTION 2021, you must leave blank lines 20b, 20c, 20d,
pired; Form CT-1 X, lines 20a, 22, 23, 25a, 31, 32, 39, 25b, 25c, 33, 34, 35, 36, 37, and 38.
and 40 are now reserved for future use. Lines 20a, 22,
23, 25a, 31, 32, 39, and 40 are now reserved for future The COVID-19 related credit for qualified sick and
use because the period of limitations for correcting these family leave compensation is limited to leave taken
lines has generally expired for most employers. Generally, after March 31, 2020, and before October 1, 2021,
you may correct overreported taxes on a previously filed and can no longer be claimed on Form CT-1.
Form CT-1 if you file Form CT-1 X within 3 years of the Generally, the credit for qualified sick and family leave
date Form CT-1 was filed or 2 years from the date you compensation, as enacted under the Families First
paid the tax reported on Form CT-1, whichever is later. Coronavirus Response Act (FFCRA) and amended and
You may correct underreported taxes on a previously filed extended by the COVID-related Tax Relief Act of 2020, for
Form CT-1 if you file Form CT-1 X within 3 years of the leave taken after March 31, 2020, and before April 1,
date the Form CT-1 was filed. We call each of these time 2021, and the credit for qualified sick and family leave
frames a period of limitations. For purposes of the period compensation under sections 3131, 3132, and 3133 of
of limitations, Form CT-1 for a calendar year is considered the Internal Revenue Code, as enacted under the
filed on the last day of February of the succeeding year if American Rescue Plan Act of 2021 (the ARP), for leave
filed before that date. For an example of the period of taken after March 31, 2021, and before October 1, 2021,
limitations, see Is There a Deadline for Filing Form CT-1 X, have expired. However, employers that pay qualified sick
later. Before using any line on Form CT-1 X, you must and family leave compensation in a later year for leave
consider if the period of limitations, as described above, is taken after March 31, 2020, and before October 1, 2021,
still open for the year that you’re correcting. are eligible to claim a credit for qualified sick and family
Lines 22 and 23 were previously used to correct the leave compensation paid in that year. Effective for tax
deferred amount of the Tier 1 Employer and Tier 1 periods beginning after December 31, 2023, the lines
Employee tax for 2020. The period of limitations for used to claim the credit for qualified sick and family leave
making corrections to the deferred amount of the Tier 1 compensation were removed from Form CT-1 because it
Employer and Tier 1 Employee tax generally expired for would be extremely rare for an employer to pay
most employers on February 29, 2024. These instructions compensation after December 31, 2023, for qualified sick
no longer discuss these deferrals. If you think that the and family leave taken after March 31, 2020, and before
period of limitations is still open for correcting your 2020 October 1, 2021. Instead, if you're eligible to claim the
Form CT-1, you can still file the March 2024 revision of credit for qualified sick and family leave compensation
Form CT-1 X to use lines 22 and 23. because you paid the compensation after December 31,
2023, for an earlier applicable leave period, file Form CT-1
Lines 20a, 25a, 31, 32, 39, and 40 were used only X to claim the credit for qualified sick and family leave
when correcting qualified compensation paid for the compensation for the year that you paid the compensation
Instructions for Form CT-1 X (Rev. 4-2025) Catalog Number 20339E
Mar 17, 2025 Department of the Treasury Internal Revenue Service www.irs.gov
after you file Form CT-1. Filing a Form CT-1 X before filing credit using Worksheet 1. You'll also use this worksheet to
a Form CT-1 for the year may result in errors or delays in figure this credit if you’re claiming it for the first time on
processing your Form CT-1 X. Form CT-1 X. If you claimed the credit for qualified sick
You will also continue to use Form CT-1 X to make and family leave compensation for leave taken after March
corrections to the credit for qualified sick and family leave 31, 2021, and before October 1, 2021, and you make any
compensation for earlier years if the period of limitations is corrections on Form CT-1 X to amounts used to figure this
still open. Corrections to amounts reported on Form CT-1, credit, you'll need to refigure the amount of this credit
lines 16, 23, 30, 31, 32, and 33, for the credit for qualified using Worksheet 2. You'll also use this worksheet to figure
sick and family leave compensation for leave taken after this credit if you’re claiming it for the first time on Form
March 31, 2020, and before April 1, 2021, are reported on CT-1 X. If you claimed the COBRA premium assistance
Form CT-1 X, lines 19, 24, 27, 28, 29, and 30, credit and you make any corrections on Form CT-1 X to
respectively. Corrections to amounts reported on Form amounts used to figure this credit, you'll need to refigure
CT-1, lines 17b, 24b, 36, 37, 38, 39, 40, and 41, for the the amount of this credit using Worksheet 3. You'll also
credit for qualified sick and family leave compensation for use this worksheet to figure this credit if you’re claiming it
leave taken after March 31, 2021, and before October 1, for the first time on Form CT-1 X.
2021, are reported on Form CT-1 X, lines 20b, 25b, 33,
34, 35, 36, 37, and 38, respectively. Employee consents to support a claim for refund.
Rev. Proc. 2017-28, 2017-14 I.R.B. 1061, available at
Credit for COBRA premium assistance payments is IRS.gov/irb/2017-14_IRB#RP-2017-28, provides
limited to periods of coverage beginning on or after guidance to employers on the requirements for employee
April 1, 2021, through periods of coverage beginning consents used by an employer to support a claim for
on or before September 30, 2021. Section 9501 of the refund of overcollected Railroad Retirement Tax Act
ARP provides for COBRA premium assistance in the form (RRTA) taxes. The revenue procedure clarifies the basic
of a full reduction in the premium otherwise payable by requirements for both a request for employee consent and
certain individuals and their families who elect COBRA for the employee consent, and permits a consent to be
continuation coverage due to a loss of coverage as the requested, furnished, and retained in an electronic format
result of a reduction in hours or an involuntary termination as an alternative to paper format. The revenue procedure
of employment (assistance eligible individuals). This also contains guidance concerning when an employer
COBRA premium assistance was available for periods of may claim a refund of only the employer share of
coverage beginning on or after April 1, 2021, through overcollected RRTA taxes. The revenue procedure
periods of coverage beginning on or before September requires that any request for consent include an Additional
30, 2021. A premium payee was entitled to the COBRA Medicare Tax notice indicating that any claim on the
premium assistance credit at the time an eligible individual employee’s behalf won’t include a claim for overpaid Tier 1
elects coverage. Therefore, other than in rare Employee Additional Medicare Tax.
circumstances, due to the COBRA notice and election
period requirements (generally, employers have 60 days Correcting Tier 1 Employee Additional Medicare Tax
to provide notice and assistance eligible individuals have withholding and compensation subject to Tier 1 Em-
60 days to elect coverage), January 2022 was generally ployee Additional Medicare Tax withholding.
the end of the period in which an assistance eligible Compensation (including tips) and sick pay subject to Tier
individual would have elected coverage. Under some rare 1 Employee Additional Medicare Tax withholding are
circumstances, it may be possible for a premium payee to reported on Form CT-1, lines 6 and 12. Certain errors
become entitled to the COBRA premium assistance credit discovered on a previously filed Form CT-1 are corrected
after January 2022. In these rare instances, the credit was on Form CT-1 X, lines 11 and 17. However, you can’t file
still claimed on Form CT-1 filed for 2022 and an Form CT-1 X to correct Tier 1 Employee Additional
adjustment, if needed, can be made on Form CT-1 X for Medicare Tax actually withheld from an employee in a
2022. Employers eligible to claim the COBRA premium prior year. See the instructions for lines 11 and 17, later,
assistance credit after 2022 must file Form CT-1 X to for more information on the types of errors that can be
claim the credit. corrected and how the correction is reported on Form
CT-1 X. For more information about Tier 1 Employee
For more information on COBRA premium assistance Additional Medicare Tax withholding, see the Instructions
payments and the credit, see Notice 2021-31, 2021-23 for Form CT-1 or go to IRS.gov/ADMTfaqs.
I.R.B. 1173, available at IRS.gov/irb/
2021-23_IRB#NOT-2021-31; and Notice 2021-46,
2021-33 I.R.B. 303, available at IRS.gov/irb/ General Instructions:
2021-33_IRB#NOT-2021-46. Understanding Form CT-1 X
Corrections to amounts reported on Form CT-1, lines
17c, 17d, and 24c, for the COBRA premium assistance What Is the Purpose of Form CT-1 X?
credit are reported on Form CT-1 X, lines 20c, 20d, and
25c, respectively. Use Form CT-1 X to correct errors on a previously filed
Form CT-1. Use Form CT-1 X to correct:
If you claimed the credit for qualified sick and • Tier 1 Employee tax, Tier 1 Employee Medicare tax,
! family leave compensation for leave taken after Tier 1 Employee Additional Medicare Tax, and Tier 2
CAUTION March 31, 2020, and before April 1, 2021, and you
Employee tax;
make any corrections on Form CT-1 X to amounts used to
figure this credit, you'll need to refigure the amount of this
2 Instructions for Form CT-1 X (Rev. 4-2025)
• Tier 1 Employer tax, Tier 1 Employer Medicare tax, and underreported tax amounts only and a second Form CT-1
Tier 2 Employer tax; X correcting the overreported tax amounts.
• Amounts reported on Form CT-1 for the credit for You’ll use the adjustment process if you underreported
qualified sick and family leave compensation for leave RRTA taxes and are making a payment, or if you
taken after March 31, 2020, and before April 1, 2021, overreported RRTA taxes and will be applying the credit to
including adjustments to Form CT-1, lines 16, 23, 30, 31, Form CT-1 for the period during which you file Form CT-1
32, and 33; X. However, see the Caution under Is There a Deadline for
• Amounts reported on Form CT-1 for the credit for Filing Form CT-1 X, later, if you’re correcting overreported
qualified sick and family leave compensation for leave tax amounts during the last 90 days of a period of
taken after March 31, 2021, and before October 1, 2021, limitations. You’ll use the claim process if you overreported
including adjustments to Form CT-1, lines 17b, 24b, 36, RRTA taxes and are requesting a refund or abatement of
37, 38, 39, 40, and 41; and the overreported tax amount. Follow the chart on page 6
• Amounts reported on Form CT-1 for the COBRA of Form CT-1 X for help in choosing whether to use the
premium assistance credit, for periods of coverage adjustment process or the claim process. Be sure to
beginning on or after April 1, 2021, through periods of provide a detailed explanation on line 43 for each
coverage beginning on or before September 30, 2021, correction that you show on Form CT-1 X.
including adjustments to Form CT-1, lines 17c, 17d, and
24c. Continue to report current year adjustments on Form
CT-1, line 14.
Use Form 843, Claim for Refund and Request for
Abatement, to request a refund or abatement of assessed You have additional requirements to complete when
interest or penalties. Don’t request a refund or abatement filing Form CT-1 X, such as certifying that you filed (or will
of assessed interest or penalties on Form CT-1 or Form file) all applicable Forms W-2, Wage and Tax Statement,
CT-1 X. and Forms W-2c, Corrected Wage and Tax Statement,
with the Social Security Administration (SSA). For
We use the terms “correct” and “corrections” on corrections of overreported Tier 1 and Tier 2 taxes, you
TIP Form CT-1 X and in these instructions to include must make any certifications that apply to your situation.
interest-free adjustments under sections 6205 and
6413 and claims for refund and abatement under sections Be sure to give us a detailed explanation on line 43 for
6402, 6414, and 6404. See Rev. Rul. 2009-39 for each correction you show on Form CT-1 X.
examples of how the interest-free adjustment and claim Don’t use Form CT-1 X to correct Form 941,
for refund rules apply in 10 different situations. You can 941-SS, 943, 944, or 945. Instead, use the "X"
find Rev. Rul. 2009-39, 2009-52 I.R.B. 951 at IRS.gov/irb/
!
CAUTION form that corresponds to those forms (Form
2009-52_IRB#RR-2009-39. 941-X, 943-X, 944-X, or 945-X).
When you discover an error on a previously filed Form
CT-1, you must:
Where Can You Get Help?
• Correct that error using Form CT-1 X; For help filing Form CT-1 X or for questions about RRTA
• File a separate Form CT-1 X for each Form CT-1 that taxes and tax corrections, you can:
you’re correcting; and • Go to IRS.gov/EmploymentTaxes and IRS.gov/
• Generally, file Form CT-1 X separately. Don’t file Form CorrectingEmploymentTaxes;
CT-1 X with Form CT-1. However, see the instructions for • See Pub. 15, Employer's Tax Guide; or
line 42, later, for an exception. • Call the IRS Business and Specialty Tax Line toll free at
If you didn’t file a Form CT-1 for 1 or more years, don’t 800-829-4933 or 800-829-4059 (TDD/TTY for persons
use Form CT-1 X. Instead, file Form CT-1 for each of who are deaf, hard of hearing, or have a speech
those years. Also, see When Should You File Form CT-1 disability), Monday–Friday from 7:00 a.m. to 7:00 p.m.
X, later. However, if you didn’t file Forms CT-1 because local time (Alaska and Hawaii follow Pacific time).
you improperly treated workers as independent See also How Can You Get Forms, Instructions, and
contractors or nonemployees and are now reclassifying Publications From the IRS, later.
them as employees, see the instructions for line 42, later.
When Should You File Form CT-1 X?
Unless otherwise specified in these instructions,
TIP an underreported employment tax credit should File Form CT-1 X when you discover an error on a
be treated like an overreported tax amount. An previously filed Form CT-1.
overreported employment tax credit should be treated like
However, if your only errors on Form CT-1 relate to
an underreported tax amount. For more information,
RRTA tax liabilities reported in Part II of Form CT-1 or on
including which process to select on lines 1 and 2, see
Form 945-A, Annual Record of Federal Tax Liability, don’t
Correcting an employment tax credit, later.
file Form CT-1 X. To correct federal tax liabilities reported
in Part II of Form CT-1, file Form 945-A, but only enter the
Report the correction of underreported and
monthly totals. The daily entries aren’t required. For more
overreported tax amounts for the same tax period on a
information about correcting RRTA tax liabilities reported
single Form CT-1 X, unless you’re requesting a refund or
on Form 945-A, see the Instructions for Form 945-A.
abatement. If you’re requesting a refund or abatement and
are correcting both underreported and overreported tax Due dates. The due date for filing Form CT-1 X depends
amounts, file one Form CT-1 X correcting the on when you discover an error and if you underreported or
Instructions for Form CT-1 X (Rev. 4-2025) 3
overreported tax. If you underreported tax, see Form CT-1 X can’t be used to correct overreported
Underreported tax, later. For overreported tax amounts, ! amounts of Tier 1 Employee Additional Medicare
you may choose to either make an interest-free CAUTION Tax unless the amounts weren’t withheld from
adjustment or file a claim for refund or abatement. If you’re employee compensation.
correcting overreported tax amounts, see Overreported
tax—Adjustment process or Overreported tax—Claim Example—You want your credit applied to Form
process, later. CT-1. You filed your 2024 Form CT-1 on February 24,
2025, and payments were timely made. On May 5, 2025,
If any due date falls on a Saturday, Sunday, or legal
you discover that you overreported tax on your 2024 Form
holiday, you may file Form CT-1 X on the next business
CT-1. You file Form CT-1 X on June 3, 2025, and check
day. The term “legal holiday” means any legal holiday in
the box on line 1 to indicate you want to use the
the District of Columbia. See Pub. 15 for the list of legal
adjustment process. The IRS treats your credit as a tax
holidays. If we receive Form CT-1 X after the due date, we
deposit made on January 1, 2025. When you file your
will treat Form CT-1 X as filed on time if the envelope
2025 Form CT-1, include the amount from Form CT-1 X,
containing Form CT-1 X is properly addressed, contains
line 26, on the “Total railroad retirement tax deposits” line
sufficient postage, and is postmarked by the U.S. Postal
of your 2025 Form CT-1.
Service (USPS) on or before the due date, or sent by an
IRS-designated private delivery service (PDS) on or Overreported tax—Claim process. If you overreported
before the due date. If you don’t follow these guidelines, tax on Form CT-1, you may choose to file a claim for
we will consider Form CT-1 X filed when it is actually refund or abatement on Form CT-1 X any time before the
received. For more information about PDSs, see Where period of limitations on credit or refund for Form CT-1
Should You File Form CT-1 X, later. expires. If you also need to correct any underreported tax
amounts, you must file another Form CT-1 X reporting
Underreported tax. If you’re correcting underreported
only corrections to the underreported tax amounts. See Is
tax, you must file Form CT-1 X by the due date of the
There a Deadline for Filing Form CT-1 X, later.
return for the return period in which you discovered the
error and pay the amount you owe by the time you file. You may not file a refund claim to correct Tier 1
Filing and paying on time generally will ensure that your ! Employee Additional Medicare Tax actually
correction is interest free and not subject to failure-to-pay CAUTION withheld from employees.
(FTP) or failure-to-deposit (FTD) penalties. See What
About Penalties and Interest, later. For details on how to Is There a Deadline for Filing Form
make a payment, see the instructions for line 26, later.
If Form CT-1 X is filed late (after the due date of the
CT-1 X?
return for the return period in which you discovered the Generally, you may correct overreported taxes on a
error), you must attach an amended Form 945-A to Form previously filed Form CT-1 if you file Form CT-1 X within 3
CT-1 X. Otherwise, the IRS may assess an “averaged” years of the date Form CT-1 was filed or 2 years from the
FTD penalty. See “Averaged” FTD penalty in section 11 of date you paid the tax reported on Form CT-1, whichever is
Pub. 15 for more information about “averaged” FTD later. You may correct underreported taxes on a previously
penalties. The total tax reported on Form 945-A, line M, filed Form CT-1 if you file Form CT-1 X within 3 years of
must match the corrected total tax (Form CT-1, line 15 the date the Form CT-1 was filed. We call each of these
(line 19 for tax years 2020–2023), combined with any time frames a period of limitations. For purposes of the
correction reported on Form CT-1 X, line 21) for the year, period of limitations, Form CT-1 is considered filed on the
less any previous abatements and interest-free tax last day in February of the succeeding year if filed before
assessments. that date.
Example—You owe tax. On March 14, 2025, you Example. You filed your 2022 Form CT-1 on January
discovered that you underreported $1,000 of RRTA 30, 2023, and payments were timely made. The IRS treats
compensation on your 2024 Form CT-1. File Form CT-1 X the return as if it were filed on February 28, 2023. On
and pay the amount you owe by March 2, 2026 (February January 15, 2026, you discover that you overreported
28, 2026, is a Saturday), because you discovered the RRTA compensation on that form by $10,000. To correct
error in 2025, and March 2, 2026, is the due date for that the error, you must file Form CT-1 X by March 2, 2026
year. If you file Form CT-1 X before March 2, 2026, pay the (February 28, 2026, is a Saturday), which is the end of the
amount you owe by the time you file. period of limitations, and use the claim process.
Form CT-1 X can’t be used to correct If you file Form CT-1 X to correct overreported tax
! underreported amounts of Tier 1 Employee ! amounts in the last 90 days of a period of
CAUTION Additional Medicare Tax unless the amounts were CAUTION limitations, you must use the claim process. You
withheld from employee compensation. can’t use the adjustment process. If you are also
correcting underreported tax amounts, you must file
Overreported tax—Adjustment process. If you another Form CT-1 X to correct the underreported tax
overreported tax and choose to apply the credit to Form amounts using the adjustment process and pay any tax
CT-1, file an adjusted return on Form CT-1 X as soon as due.
possible after you discover the error but more than 90
days before the period of limitations on the credit or refund
for Form CT-1 expires. See Is There a Deadline for Filing
Where Should You File Form CT-1 X?
Form CT-1 X, later. Send your completed Form CT-1 X to:
4 Instructions for Form CT-1 X (Rev. 4-2025)
Department of the Treasury How Should You Report Negative Amounts?
Internal Revenue Service Center Form CT-1 X uses negative numbers to show reductions
Cincinnati, OH 45999-0007 in tax (credits) and positive numbers to show additional
tax (amounts you owe).
PDSs can’t deliver to P.O. boxes. You must use the USPS
to mail an item to a P.O. box address. Go to IRS.gov/PDS When reporting a negative amount in columns 3 and 4,
for the current list of PDSs. If you file Form CT-1 X using a use a minus sign instead of parentheses. For example,
PDS, send it to the following address. enter “-10.59” instead of “(10.59).” However, if you’re
completing the return on your computer and your software
Ogden-Internal Revenue Submission Processing only allows you to use parentheses to report negative
Center amounts, you may use them.
1973 Rulon White Blvd.
Ogden, UT 84201 How Should You Make Entries on Form CT-1 X?
You can help the IRS process Form CT-1 X timely and
Use this address even though Form CT-1 X mailed accurately if you follow these guidelines.
through the USPS goes to Cincinnati. • Type or print your entries.
• Use Courier font (if possible) for all typed or
How Should You Complete Form CT-1 computer-generated entries.
X? • Omit dollar signs. You may use commas and decimal
points, if desired. Enter dollar amounts to the left of any
Use a Separate Form CT-1 X for Each Year You’re preprinted decimal point and cents to the right of it.
Correcting • Always show an amount for cents, even if it is zero.
Don’t round entries to whole dollars.
Use a separate Form CT-1 X for each Form CT-1 that
• Complete all five pages and sign Form CT-1 X on
you’re correcting. For example, if you found errors on your page 5.
Forms CT-1 for 2023 and 2024, file one Form CT-1 X to
• Staple multiple sheets in the upper-left corner.
correct the 2023 Form CT-1. File a second Form CT-1 X to
correct the 2024 Form CT-1. What About Penalties and Interest?
Employer Identification Number (EIN), RRB Generally, your correction of an underreported tax amount
won’t be subject to an FTP penalty, an FTD penalty, or
Number, Name, and Address interest if you:
Enter your EIN, RRB number, name, and address in the • File on time (by the due date of the year in which you
spaces provided. Also enter your name and EIN on the discover the error),
top of pages 2, 3, 4, and 5, and on any attachments. If • Pay the amount shown on line 26 by the time you file
your address has changed since you filed your Form Form CT-1 X,
CT-1, enter the corrected information and the IRS will • Enter the date you discovered the error, and
update your address of record. Be sure to write your • Explain in detail the grounds and facts relied on to
name, EIN, “Form CT-1 X,” and the calendar year you’re support the correction.
correcting on the top of any attachments.
No correction will be eligible for interest-free treatment
Return You’re Correcting if any of the following apply.
Enter the calendar year of the Form CT-1 you’re correcting • The underreported amounts relate to an issue that was
in the box at the top of page 1. Enter the same calendar raised in an examination of a prior period.
year on pages 2, 3, 4, and 5. • You knowingly underreported your employment tax
liability.
Enter the Date You Discovered Errors • You received a notice and demand for payment.
You must enter the date you discovered errors. You • You received a notice of determination under section
discover an error when you have enough information to be 7436.
able to correct it. If you’re reporting several errors that you If you receive a notice about a penalty after you file this
discovered at different times, enter the earliest date you return, reply to the notice with an explanation and we will
discovered an error here. Report any subsequent dates determine if you meet reasonable-cause criteria. Don’t
and related errors on line 43. attach an explanation when you file your return.
Must You Make an Entry on Each Line? Overview of the Process
You must provide all of the information requested at the
top of page 1 of Form CT-1 X. You must check one box To correct a previously filed Form CT-1, use Form CT-1 X
(but not both) in Part 1. In Part 2, you must check the box to file either an adjusted railroad retirement tax return or a
on line 3 and any applicable boxes on lines 4 and 5. In claim for refund or abatement. The adjustment process
Part 3, if any line doesn’t apply, leave it blank. Complete and the claim process are outlined below.
Parts 4 and 5 as instructed. If you underreported the tax. If you underreported
the tax on a previously filed Form CT-1, check the box on
line 1 and pay any additional amount you owe by the
time you file Form CT-1 X. For details on how to make a
payment, see the instructions for line 26, later.
Instructions for Form CT-1 X (Rev. 4-2025) 5
Example—You underreported RRTA taxes. On June If you’re correcting both underreported tax amounts
20, 2025, you discovered an error that results in additional and overreported tax amounts on this form, you must
tax on your 2024 Form CT-1. File Form CT-1 X by March check this box. If you check this box, any negative amount
2, 2026 (February 28, 2026, is a Saturday), and pay the shown on line 26 will be applied as a credit (tax deposit) to
amount you owe by the time you file. See When Should your Form CT-1 for the year in which you’re filing this form.
You File Form CT-1 X, earlier. Don’t attach Form CT-1 X to See Example—You want your overreported tax applied as
your 2025 Form CT-1. a credit on Form CT-1, earlier.
If you overreported the tax. If you overreported the Form CT-1 X can’t be used to correct overreported
tax on a previously filed Form CT-1, choose one of the amounts of Tier 1 Employee Additional Medicare
following options. !
CAUTION Tax unless the amounts weren’t withheld from
• Use the adjustment process. Check the box on line 1 to employee compensation.
apply any credit (negative amount) from line 26 to Form
CT-1 for the year during which you file Form CT-1 X. If you owe tax. Pay the amount shown on line 26 by the
• Use the claim process. Check the box on line 2 to file a time you file Form CT-1 X. Generally, you won’t be
claim on Form CT-1 X requesting a refund or abatement of charged interest if you file on time, pay on time, enter the
the amount shown on line 26. date you discovered the error, and explain the correction
To ensure that the IRS has enough time to on line 43.
TIP process a credit for an overreporting tax If you have a credit. You overreported RRTA taxes (you
adjustment in the year during which you file Form have a negative amount on line 26) and want the IRS to
CT-1 X, you’re encouraged to file Form CT-1 X correcting apply the credit to Form CT-1 for the period during which
the overreported tax amount in the first 11 months of a you filed Form CT-1 X. The IRS will apply your credit on
year. For example, if you discover an overreported tax the first day of the Form CT-1 year during which you filed
amount in December, you may want to file Form CT-1 X in Form CT-1 X. However, the credit you show on Form CT-1
the first 11 months of the next year. However, there must X, line 26, may not be fully available on your Form CT-1 if
be 90 days remaining on the period of limitations when the IRS corrects it during processing or you owe other
you file Form CT-1 X. See the Caution under Is There a taxes, penalties, or interest. The IRS will notify you if your
Deadline for Filing Form CT-1 X, earlier. This should claimed credit changes or if the amount available as a
ensure that the IRS will have enough time to process the credit on Form CT-1 was reduced because of unpaid
Form CT-1 X so that the credit will be posted before you taxes, penalties, or interest.
file Form CT-1, thus avoiding an erroneous balance due
notice from the IRS. See the example next. Don’t check the box on line 1 if you’re correcting
! overreported tax amounts and the period of
Example—You want your overreported tax applied CAUTION limitations on credit or refund for Form CT-1 will
as a credit on Form CT-1. On December 19, 2025, you expire within 90 days of the date you file Form CT-1 X.
discover you overreported your tax on your 2024 Form Instead, check the box on line 2. See Is There a Deadline
CT-1 and want to choose the adjustment process. To for Filing Form CT-1 X, earlier.
allow the IRS enough time to process the credit, you file
Form CT-1 X on March 10, 2026, and take the credit on 2. Claim
your 2026 Form CT-1. Check the box on line 2 to use the claim process if you’re
correcting overreported tax amounts only and you’re
Specific Instructions claiming a refund or abatement for the negative amount
(credit) shown on line 26. Don’t check this box if you’re
Part 1: Select ONLY One Process correcting any underreported tax amounts on this form.
Because Form CT-1 X may be used to file either an You must check the box on line 2 if you have a credit (a
adjusted railroad retirement tax return or a claim for refund negative amount on line 26) and the period of limitations
or abatement, you must check one box on either line 1 or on credit or refund for Form CT-1 will expire within 90 days
line 2. Don’t check both boxes. of the date you file Form CT-1 X. See Is There a Deadline
for Filing Form CT-1 X, earlier.
Correcting an employment tax credit. For boxes 1 and
2, if you underreported an employment tax credit, treat it The IRS usually processes claims shortly after they are
like you overreported a tax amount. If you overreported an filed. The IRS will notify you if your claim is denied,
employment tax credit, treat it like you underreported a tax accepted as filed, or selected to be examined. See Pub.
amount. If you're filing Form CT-1 X to adjust only an 556, Examination of Returns, Appeal Rights, and Claims
employment tax credit and you're not correcting any for Refund, for more information.
overreported taxes on Form CT-1 X, lines 6–17, skip lines
4 and 5. Unless the IRS corrects Form CT-1 X during
processing or you owe other taxes, penalties, or interest,
1. Adjusted Railroad Retirement Tax Return the IRS will refund the amount shown on line 26, plus any
Check the box on line 1 if you’re correcting underreported interest that applies.
tax amounts or overreported tax amounts and you would You may not file a refund claim to correct Tier 1
like to use the adjustment process to correct the errors. Employee Additional Medicare Tax actually
!
CAUTION withheld from employees.
6 Instructions for Form CT-1 X (Rev. 4-2025)
Part 2: Complete the Certifications received written statements from the employees stating
that they didn’t and won’t receive a refund or credit for the
You must complete all certifications that apply by checking prior year taxes. Don’t send these statements to the IRS.
the appropriate boxes. If all of your corrections relate to Keep them for your records. Generally, all employment tax
underreported tax amounts, complete line 3 only; skip records must be kept for at least 4 years. Records related
lines 4 and 5 and go to Part 3. to qualified sick leave compensation and qualified family
leave compensation for leave taken after March 31, 2021,
If your corrections relate to overreported tax amounts,
and before October 1, 2021, should be kept for at least 6
other than corrections related to underreported
years. Copies must be submitted to the IRS if requested.
employment tax credits, you have a duty to ensure that
your employees' rights to recover overpaid Employee 4b. Check the box on line 4b to certify that your
RRTA taxes that you withheld are protected. The overreported amount is only for Employer RRTA taxes on
certifications on lines 4 and 5 address the requirement to: those employees whom you were unable to find or those
who didn’t give you a statement described on line 4a.
• Repay or reimburse your employees for the
overcollection of Employee RRTA taxes, or 4c. Check the box on line 4c to certify that your
• Obtain consents from your employees to file a claim on overreported amount is only for RRTA taxes and/or Tier 1
their behalf. See Rev. Proc. 2017-28 for guidance on the Employee Additional Medicare Tax that you didn’t withhold
requirements for both a request for employee consent and from your employees.
for the employee consent.
For purposes of these certifications, Employee RRTA 5. Certifying Claims
taxes consist of Tier 1 Employee tax, Tier 1 Employee If you’re filing a claim for refund or abatement of
Medicare tax, and Tier 2 Employee tax. Employer RRTA overreported RRTA tax and/or Tier 1 Employee Additional
taxes consist of Tier 1 Employer tax, Tier 1 Employer Medicare Tax and checked the box on line 2, check the
Medicare tax, and Tier 2 Employer tax. appropriate box on line 5. You may need to check more
than one box. If you obtained written statements or
3. Filing Forms W-2 or Forms W-2c consents from some employees but you couldn’t locate
Check the box on line 3 to certify that you filed or will file employees or secure the statements of the remaining
Forms W-2 or Forms W-2c with the SSA, as required, employees, check all applicable boxes. Provide a
showing your employees' correct wage and tax amounts. summary on line 43 of the amount of the corrections for
See the General Instructions for Forms W-2 and W-3 for the employees who provided statements or consents and
detailed information about filing requirements. those who didn’t.
You must check the box on line 3 to certify that you filed You may not file a refund claim to correct Tier 1
Forms W-2 or Forms W-2c even if your corrections on ! Employee Additional Medicare Tax actually
Form CT-1 X don’t change amounts shown on those CAUTION withheld from employees. If you request their
forms. For example, if your only correction to Form CT-1 consent to file a claim for employee RRTA taxes you must
involves misstated tax adjustments, which don’t change tell your employees that you can’t claim a refund of any
the amounts reported on your employees’ Forms W-2 (see Tier 1 Employee Additional Medicare Tax on their behalf.
the instructions for line 18, later), check the box on line 3 See Rev. Proc. 2017-28 for sample language to use in
to certify that you already filed all required Forms W-2 and your request.
W-2c with the SSA. In this situation, you’re certifying that
you don’t need to file Form W-2c because you already 5a. Check the box on line 5a if your overreported tax
filed a correct Form W-2. includes overcollected Employee RRTA taxes for each
affected employee. You’re certifying that you repaid or
4. Certifying Overreporting Adjustments reimbursed the employees their shares of the prior year
If you overreported RRTA tax and/or Tier 1 Employee Employee RRTA taxes and you received written
Additional Medicare Tax and checked the box on line 1, statements from those employees stating that they didn’t
check the appropriate box on line 4. You may need to and won’t receive a refund or credit for the prior year
check more than one box. If you obtained written taxes. Don’t send these statements to the IRS. Keep them
statements from some employees but you couldn’t locate for your records. Generally, all employment tax records
employees or secure the statements of the remaining must be kept for at least 4 years. Records related to
employees, check all applicable boxes. Provide a qualified sick leave compensation and qualified family
summary on line 43 of the amount of the corrections for leave compensation for leave taken after March 31, 2021,
both the employees who provided written statements and and before October 1, 2021, should be kept for at least 6
for those who didn’t. years. Copies must be submitted to the IRS if requested.
You may not use Form CT-1 X to correct 5b. Check the box on line 5b if your overreported tax
overreported amounts of Tier 1 Employee includes overcollected prior year Employee RRTA taxes
!
CAUTION Additional Medicare Tax unless the amounts for each affected employee and you haven’t yet repaid or
weren’t withheld from employee compensation. reimbursed the Employee RRTA taxes. You’re certifying
that you received consent from each affected employee to
4a. Check the box on line 4a if your overreported amount file a claim on the employee share of those taxes and you
includes each affected employee share of overcollected received written statements from those employees stating
Employee RRTA taxes. You’re certifying that you repaid or that they didn’t and won’t receive a refund or credit for the
reimbursed the prior year Employee RRTA taxes and you prior year taxes.
Instructions for Form CT-1 X (Rev. 4-2025) 7
An employee consent must: instructions for each line carefully before entering amounts
• Contain the name, address, and social security number in the columns.
(or truncated taxpayer identification number, when
If any line doesn’t apply to you, leave it blank.
appropriate) of the employee;
• Contain the name, address, and EIN of the employer; If you previously adjusted or amended Form CT-1
• Contain the tax period(s), the type of tax, and the ! using Form CT-1 X, or because of an IRS
amount of tax for which the consent is provided; CAUTION examination change, show amounts in column 2
• Affirmatively state that the employee authorizes the that include those previously reported corrections.
employer to claim a refund for the overpayment of the
employee share of tax; 6. Tier 1 Employer Tax—Compensation
• Include the employee's written statement certifying that
the employee hasn't made any previous claims (or the For purposes of these instructions, all references
claims were rejected) and won't make any future claims for TIP to “sick pay” mean ordinary sick pay, not “qualified
refund or credit of the amount of the overcollection; sick leave compensation.”
• Identify the basis of the claim; and If you’re correcting the compensation (other than tips
• Be dated and contain the employee's signature under and sick pay) for the Tier 1 Employer tax you reported on
penalties of perjury. The penalties of perjury statement Form CT-1, line 1, enter the total corrected amount for all
should be located immediately above the required employees in column 1. In column 2, enter the amount you
signature. originally reported or as previously corrected. In column 3,
Don’t send these statements and consents to the IRS. enter the difference between columns 1 and 2. If you (or
Keep them for your records. Generally, all employment tax the IRS) previously corrected the amount reported on
records must be kept for at least 4 years. Records related Form CT-1, line 1, enter in column 2 the amount after any
to qualified sick leave compensation and qualified family previous corrections.
leave compensation for leave taken after March 31, 2021,
and before October 1, 2021, should be kept for at least 6 line 6 (column 1)
years. Copies must be submitted to the IRS if requested. - line 6 (column 2)
In certain situations, you may not have repaid or line 6 (column 3) If the amount in column 2 is larger than
reimbursed your employees or obtained their consents the amount in column 1, use a minus
prior to filing a claim, such as in cases where the period of sign in column 3.
limitations on credit or refund is about to expire. In those
situations, file Form CT-1 X but don’t check a box on
line 5. Tell us on line 43 that you haven’t repaid or Multiply the amount in column 3 by 0.062 (6.2% tax
reimbursed employees or obtained consents at the time rate) and enter the result in column 4.
you file the claim. However, you must repay or reimburse
your employees and certify that you have done so before line 6 (column 3)
the IRS can allow the claim. x 0.062
5c. Check the box on line 5c to certify that your line 6 (column 4) If the amount in column 3 used a minus sign,
overreported tax is only for the Employer RRTA taxes. This also use a minus sign in column 4.
applies when affected employees didn’t give you consent
to file a claim for refund for the Employee RRTA taxes,
they couldn’t be found, or they didn’t give you a statement Example—Tier 1 Employer compensation
described on line 5b. decreased. You reported $9,000 as Tier 1 Employer
compensation in computing the tax on line 1 of your 2024
5d. Check the box on line 5d to certify that your Form CT-1. In December 2025, you discovered that you
overreported amount is only for RRTA taxes and/or Tier 1 included $2,000 in compensation for one of your
Employee Additional Medicare Tax that you didn’t withhold employees twice. To correct the error, figure the difference
from your employees. on Form CT-1 X as shown.
Part 3: Enter the Corrections for the
Column 1 (corrected amount) 7,000.00
Calendar Year You’re Correcting Column 2 (Form CT-1, line 1) - 9,000.00
Column 3 (difference) -2,000.00
What Amounts Should You Report in Part 3?
On lines 6–17, columns 1 and 2, show amounts for all of
your employees, not just for those employees whose Use the difference in column 3 to determine your tax
amounts you’re correcting. correction.
If a correction that you report in column 4 includes both
Column 3 (difference) -2,000.00
underreported and overreported amounts (see the
Tax rate (6.2%) x 0.062
instructions for line 41, later), provide details for each error
on line 43. Column 4 (tax correction) -124.00
Because special circumstances apply for lines 18, 19,
20b–20d, 24, 25b, 25c, 27–30, and 33–38, read the
8 Instructions for Form CT-1 X (Rev. 4-2025)
Be sure to explain the reasons for this correction on line 8 (column 1)
line 43. - line 8 (column 2)
line 8 (column 3) If the amount in column 2 is larger
7. Tier 1 Employer Medicare
than the amount in column 1, use a
Tax—Compensation minus sign in column 3.
If you’re correcting the compensation (other than tips and
sick pay) for the Tier 1 Employer Medicare tax you
reported on Form CT-1, line 2, enter the total corrected Multiply the amount in column 3 by the rate stated on
amount in column 1. In column 2, enter the amount you line 3 of the Form CT-1 for the year that you’re
originally reported or as previously corrected. In column 3, correcting and enter the result in column 4. If the amount
enter the difference between columns 1 and 2. in column 3 used a minus sign, also use a minus sign in
column 4.
line 7 (column 1)
Example—Tier 2 Employer compensation
- line 7 (column 2)
decreased. Following Example—Tier 1 Employer
line 7 (column 3) If the amount in column 2 is larger compensation decreased in the instructions for line 6, the
than the amount in column 1, use a
compensation that you counted twice was also Tier 2
minus sign in column 3.
Employer compensation. Because you’re correcting your
2024 Form CT-1 in this example, use the rate from line 3
(13.1%) shown on that return. To correct the error, figure
Multiply the amount in column 3 by 0.0145 (1.45% tax the difference on Form CT-1 X as shown.
rate) and enter the result in column 4.
Column 1 (corrected amount) 7,000.00
line 7 (column 3) Column 2 (Form CT-1, line 3) - 9,000.00
x 0.0145
Column 3 (difference) -2,000.00
line 7 (column 4) If the amount in column 3 used a minus sign,
also use a minus sign in column 4.
Use the difference in column 3 to determine your tax
correction.
Example—Tier 1 Employer Medicare
compensation decreased. Following Example—Tier 1
Column 3 (difference) -2,000.00
Employer compensation decreased in the instructions for
Tax rate (13.1%) x 0.131
line 6, the compensation that you counted twice was also
Tier 1 Employer Medicare compensation. To correct the Column 4 (tax correction) -262.00
error, figure the difference on Form CT-1 X as shown.
Be sure to explain the reasons for this correction on
Column 1 (corrected amount) 7,000.00
line 43.
Column 2 (Form CT-1, line 2) - 9,000.00
Column 3 (difference) -2,000.00 9. Tier 1 Employee Tax—Compensation
If you’re correcting the compensation, including tips
reported, but excluding sick pay, for the Tier 1 Employee
Use the difference in column 3 to determine your tax tax you reported on Form CT-1, line 4, enter the total
correction. corrected amount in column 1. In column 2, enter the
amount you originally reported or as previously corrected.
Column 3 (difference) -2,000.00 In column 3, enter the difference between columns 1 and
Tax rate (1.45%) x 0.0145 2.
Column 4 (tax correction) -29.00
line 9 (column 1)
- line 9 (column 2)
Be sure to explain the reasons for this correction on line 9 (column 3) If the amount in column 2 is larger than
line 43. the amount in column 1, use a minus
sign in column 3.
8. Tier 2 Employer Tax—Compensation
If you’re correcting the compensation (other than tips) for
the Tier 2 Employer tax you reported on Form CT-1, line 3, Multiply the amount in column 3 by 0.062 (6.2% tax
enter the total corrected amount in column 1. In column 2, rate) and report the result in column 4.
enter the amount you originally reported or as previously
corrected. In column 3, enter the difference between
line 9 (column 3)
columns 1 and 2.
x 0.062
line 9 (column 4) If the amount in column 3 used a minus sign,
also use a minus sign in column 4.
Instructions for Form CT-1 X (Rev. 4-2025) 9
Be sure to explain the reasons for this correction on line 11 (column 1)
line 43. - line 11 (column 2)
line 11 (column 3) If the amount in column 2 is larger
10. Tier 1 Employee Medicare
than the amount in column 1, use a
Tax—Compensation minus sign in column 3.
If you’re correcting the compensation, including tips
reported, but excluding sick pay, for the Tier 1 Employee
Medicare tax you reported on Form CT-1, line 5, enter the
total corrected amount in column 1. In column 2, enter the Multiply the amount in column 3 by 0.009 (0.9% tax
amount you originally reported or as previously corrected. rate) and enter the result in column 4.
In column 3, enter the difference between columns 1 and
2. line 11 (column 3)
x 0.009
line 10 (column 1) line 11 (column 4) If the amount in column 3 used a minus sign,
- line 10 (column 2) also use a minus sign in column 4.
line 10 (column 3) If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3. Example—Prior year administrative error
(incorrectly reported amount of Tier 1 Employee
Additional Medicare Tax actually withheld). Nathan
Multiply the amount in column 3 by 0.0145 (1.45% tax Smith's compensation exceeded the $200,000
rate) and enter the result in column 4. withholding threshold for Tier 1 Employee Additional
Medicare Tax in November 2024. The total compensation
line 10 (column 3) paid to Nathan for 2024 was $230,000. You withheld $270
x 0.0145 ($30,000 x 0.009) from Nathan's compensation. However,
line 10 (column 4) If the amount in column 3 used a minus sign, on your 2024 Form CT-1 you mistakenly reported $3,000
also use a minus sign in column 4. on line 6 (Compensation column), and Tier 1 Employee
Additional Medicare Tax withheld of $27 on line 6 (Tax
column). You discovered the error on March 17, 2025.
Be sure to explain the reasons for this correction on This is an example of an administrative error that may be
line 43. corrected in a later calendar year because the amount
actually withheld differs from the amount reported on your
11. Tier 1 Employee Additional Medicare 2024 Form CT-1. Use Form CT-1 X, line 11, to correct the
Tax—Compensation (Other Than Sick Pay) error as shown.
You may use Form CT-1 X to correct errors to Tier 1
Column 1 (corrected amount) 30,000.00
Employee Additional Medicare Tax withholding for prior
Column 2 (Form CT-1, line 6 - 3,000.00
years if the amount reported on Form CT-1, line 6, isn’t the
(Compensation column))
amount you actually withheld. This type of error is an
Column 3 (difference) 27,000.00
administrative error. The administrative error adjustment
corrects the amount reported on Form CT-1 to agree with
the amount actually withheld from employees. Use the difference in column 3 to determine your tax
If a prior year error was a nonadministrative error, you correction.
may correct only the compensation subject to Tier 1
Employee Additional Medicare Tax withholding that was Column 3 (difference) 27,000.00
originally reported on Form CT-1, line 6, or previously Tax rate (0.9%) x 0.009
corrected on Form CT-1 X. You can’t correct the tax Column 4 (tax correction) 243.00
reported on Form CT-1, line 6.
Prior year administrative errors. If you’re correcting the
compensation subject to Tier 1 Employee Additional Be sure to explain the reasons for this correction on
Medicare Tax withholding that you reported on Form CT-1, line 43.
line 6, enter the total corrected amount in column 1. In Prior year nonadministrative errors. You may correct
column 2, enter the amount you originally reported or as only the compensation subject to Tier 1 Employee
previously corrected. In column 3, enter the difference Additional Medicare Tax withholding that you reported on
between columns 1 and 2. Form CT-1, line 6 (Compensation column). Enter the total
corrected amount in column 1. In column 2, enter the
amount you originally reported or as previously corrected.
In column 3, enter the difference between columns 1 and
2.
10 Instructions for Form CT-1 X (Rev. 4-2025)
line 11 (column 1) and didn’t report Leah's $20,000 in compensation subject
- line 11 (column 2) to Tier 1 Employee Additional Medicare Tax withholding
on line 6 of your 2024 Form CT-1.
line 11 (column 3) If the amount in column 2 is larger
than the amount in column 1, use a You discovered both errors on March 17, 2025. Use
minus sign in column 3. Form CT-1 X, line 11, to correct the errors as shown.
Column 1 (corrected amount) 50,000.00
Column 2 (Form CT-1, line 6 - 3,000.00
Don’t multiply the amount in column 3 by 0.009 (0.9% (Compensation column))
tax rate). Leave column 4 blank and explain the reasons Column 3 (difference) 47,000.00
for this correction on line 43.
Example—Prior year nonadministrative error
Determine the portion of compensation reported in
(failure to withhold Tier 1 Employee Additional
column 3 that is related to the administrative error
Medicare Tax when required). Leah Green's
($47,000 - $20,000 (nonadministrative error) = $27,000
compensation exceeded the $200,000 withholding
(administrative error)). Multiply this portion of column 3 by
threshold for Tier 1 Employee Additional Medicare Tax in
0.009 (0.9% tax rate) to determine your tax correction.
December 2024. The total compensation paid to Leah for
2024 was $220,000. You were required to withhold $180
($20,000 x 0.009) but you withheld nothing and didn’t Difference related to administrative error 27,000.00
report an amount on line 6 of your 2024 Form CT-1. You Tax rate (0.9%) x 0.009
discovered the error on March 17, 2025. File Form CT-1 X Column 4 (tax correction) 243.00
to correct the compensation subject to Tier 1 Employee
Additional Medicare Tax withholding for your 2024 Form
CT-1, but you may not correct the Tier 1 Employee Be sure to explain the reasons for these corrections on
Additional Medicare Tax withheld (column 4) because the line 43. You must also report that $20,000 of the amount
error involves a previous year and the amount previously shown in column 3 was related to the correction of a prior
reported for the employee represents the actual amount year nonadministrative error and $27,000 of the amount
withheld from the employee during 2024. shown in column 3 was related to the correction of an
administrative error.
Combination of prior year administrative and nonad-
ministrative errors. If you’re reporting both 12. Tier 2 Employee Tax—Compensation
administrative errors and nonadministrative errors for the If you’re correcting the compensation, including tips
same prior year, enter the total corrected amount in reported, for the Tier 2 Employee tax you reported on
column 1. In column 2, enter the amount you originally Form CT-1, line 7, enter the total corrected amount in
reported or as previously corrected. In column 3, enter the column 1. In column 2, enter the amount you originally
difference between columns 1 and 2. However, multiply reported or as previously corrected. In column 3, enter the
only the amount of compensation reported in column 3 difference between columns 1 and 2.
that is related to administrative errors by 0.009 (0.9% tax
rate). Don’t multiply any compensation reported in column
line 12 (column 1)
3 that was related to nonadministrative errors by 0.009
- line 12 (column 2)
(0.9% tax rate). Use line 43 to explain in detail your
corrections. The explanation must include the reasons for line 12 (column 3) If the amount in column 2 is larger
the corrections and a breakdown of the amount reported than the amount in column 1, use a
minus sign in column 3.
in column 3 into the amounts related to administrative
errors and nonadministrative errors.
Example—Combination of prior year Multiply the amount in column 3 by the rate stated on
administrative and nonadministrative errors. Nathan line 7 of the Form CT-1 for the year that you’re
Smith's compensation exceeded the $200,000 correcting and enter the result in column 4. If the amount
withholding threshold for Tier 1 Employee Additional in column 3 used a minus sign, also use a minus sign in
Medicare Tax in November 2024. The total compensation column 4.
paid to Nathan for 2024 was $230,000. You withheld $270
($30,000 x 0.009) from Nathan's compensation. However, Example—Tier 2 Employee compensation
on your 2024 Form CT-1, you mistakenly reported $3,000 decreased. Following Example—Tier 1 Employer
on line 6 (Compensation column), and Tier 1 Employee compensation decreased in the instructions for line 6, the
Additional Medicare Tax withheld of $27 on line 6 (Tax compensation that you counted twice was also Tier 2
column). The difference in compensation subject to Tier 1 Employee compensation. Because you’re correcting your
Employee Additional Medicare Tax related to this 2024 Form CT-1 in this example, use the rate for line 7
administrative error is $27,000 ($30,000 - $3,000). (4.9%) shown on that return. To correct the error, figure
the difference on Form CT-1 X as shown.
Leah Green's compensation exceeded the $200,000
withholding threshold for Tier 1 Employee Additional
Medicare Tax in December 2024. The total compensation
paid to Leah for 2024 was $220,000. You were required to
withhold $180 ($20,000 x 0.009) but you withheld nothing
Instructions for Form CT-1 X (Rev. 4-2025) 11
Column 1 (corrected amount) 7,000.00 Column 3 (difference) 1,000.00
Column 2 (Form CT-1, line 7) - 9,000.00 Tax rate (6.2%) x 0.062
Column 3 (difference) -2,000.00 Column 4 (tax correction) 62.00
Use the difference in column 3 to determine your tax Be sure to explain the reasons for this correction on
correction. line 43.
Column 3 (difference) -2,000.00 14. Tier 1 Employer Medicare Tax—Sick Pay
Tax rate (4.9%) x 0.049 If you’re correcting the sick pay for the Tier 1 Employer
Column 4 (tax correction) -98.00 Medicare tax you reported on Form CT-1, line 9, enter the
total corrected amount in column 1. In column 2, enter the
amount you originally reported or as previously corrected.
Be sure to explain the reasons for this correction on In column 3, enter the difference between columns 1 and
line 43. 2.
For purposes of these instructions, all references
line 14 (column 1)
TIP to “sick pay” mean ordinary sick pay, not “qualified - line 14 (column 2)
sick leave compensation.”
line 14 (column 3) If the amount in column 2 is larger
than the amount in column 1, use a
13. Tier 1 Employer Tax—Sick Pay minus sign in column 3.
If you’re correcting the sick pay for the Tier 1 Employer tax
you reported on Form CT-1, line 8, enter the total
corrected amount in column 1. In column 2, enter the Multiply the amount in column 3 by 0.0145 (1.45% tax
amount you originally reported or as previously corrected. rate) and enter the result in column 4.
In column 3, enter the difference between columns 1 and
2.
line 14 (column 3)
x 0.0145
line 13 (column 1)
line 14 (column 4) If the amount in column 3 used a minus sign,
- line 13 (column 2)
also use a minus sign in column 4.
line 13 (column 3) If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.
Be sure to explain the reasons for this correction on
line 43.
Multiply the amount in column 3 by 0.062 (6.2% tax 15. Tier 1 Employee Tax—Sick Pay
rate) and enter the result in column 4.
If you’re correcting the sick pay for the Tier 1 Employee tax
you reported on Form CT-1, line 10, enter the total
line 13 (column 3)
corrected amount in column 1. In column 2, enter the
x 0.062
amount you originally reported or as previously corrected.
line 13 (column 4) If the amount in column 3 used a minus sign, In column 3, enter the difference between columns 1 and
also use a minus sign in column 4.
2.
line 15 (column 1)
Example—Tier 1 Employer sick pay increased. You
- line 15 (column 2)
reported $8,000 as Tier 1 Employer sick pay in computing
the tax on line 8 of your 2024 Form CT-1. In December line 15 (column 3) If the amount in column 2 is larger
than the amount in column 1, use a
2025, you discover that you overlooked $1,000 in sick pay
minus sign in column 3.
for one of your employees. To correct the error, figure the
difference on Form CT-1 X as shown.
Column 1 (corrected amount) 9,000.00 Multiply the amount in column 3 by 0.062 (6.2% tax
Column 2 (Form CT-1, line 8) - 8,000.00 rate) and enter the result in column 4.
Column 3 (difference) 1,000.00
line 15 (column 3)
x 0.062
Use the difference in column 3 to determine your tax line 15 (column 4) If the amount in column 3 used a minus sign,
correction. also use a minus sign in column 4.
Be sure to explain the reasons for this correction on
line 43.
12 Instructions for Form CT-1 X (Rev. 4-2025)
16. Tier 1 Employee Medicare Tax—Sick Pay You may need to report negative numbers in any
If you’re correcting the sick pay for the Tier 1 Employee TIP column. Make sure that the difference you enter in
Medicare tax you reported on Form CT-1, line 11, enter column 3 accurately represents the change to
the total corrected amount in column 1. In column 2, enter adjustments originally reported or previously corrected on
the amount you originally reported or as previously Form CT-1, line 14.
corrected. In column 3, enter the difference between
columns 1 and 2. Copy the amount in column 3 to column 4. Include any
minus sign shown in column 3.
line 16 (column 1) On line 43, describe what you misreported on Form
- line 16 (column 2) CT-1. Tell us which current year adjustments have
line 16 (column 3) If the amount in column 2 is larger changed, that is, fractions of cents; uncollected Tier 1
than the amount in column 1, use a Employee tax, Tier 1 Employee Medicare tax, or Tier 2
minus sign in column 3. Employee tax on tips; or credits for overpayments of
penalties or interest paid on tax for earlier years.
Only use line 18 to correct adjustments for
Multiply the amount in column 3 by 0.0145 (1.45% tax
! fractions of cents; uncollected Tier 1 Employee
rate) and enter the result in column 4. CAUTION tax, Tier 1 Employee Medicare tax, Tier 1
Employee Additional Medicare Tax, and Tier 2 Employee
line 16 (column 3)
tax on tips; or credits for overpayments of penalty or
x 0.0145 interest previously reported. File a separate Form CT-1 X
line 16 (column 4) If the amount in column 3 used a minus sign, for each year being corrected.
also use a minus sign in column 4.
Form CT-1 X and these instructions use the terms
TIP “nonrefundable” and “refundable” when
Be sure to explain the reasons for this correction on discussing credits. The term “nonrefundable”
line 43. means the portion of the credit which is limited by law to
certain taxes. The term “refundable” means the portion of
17. Tier 1 Employee Additional Medicare the credit which is in excess of those taxes.
Tax—Sick Pay
You may use Form CT-1 X to correct errors to Tier 1 19. Nonrefundable Portion of Credit for Qualified
Employee Additional Medicare Tax withholding for prior Sick and Family Leave Compensation for Leave
years if the amount reported on Form CT-1, line 12, isn’t
the amount you actually withheld. This type of error is an Taken After March 31, 2020, and Before April 1,
administrative error. 2021
If a prior year error was a nonadministrative error, you Generally, the period of limitations for correcting
may correct only the sick pay subject to Tier 1 Employee ! the nonrefundable portion of credit for qualified
Additional Medicare Tax withholding that was originally CAUTION sick and family leave compensation paid in 2020
reported on Form CT-1, line 12, or previously corrected on expired on February 29, 2024, for most employers.
Form CT-1 X. You can’t correct the tax reported on Form Generally, the period of limitations for correcting the
CT-1, line 12. nonrefundable portion of credit for qualified sick and
For more information on the types of errors that can be family leave compensation paid in 2021 expired on
corrected on line 17, see the detailed examples in the February 28, 2025, for most employers. For more
instructions for line 11, earlier. information about the period of limitations, see Is There a
Deadline for Filing Form CT-1 X, earlier.
18. Tax Adjustments If you’re correcting the nonrefundable portion of the
Don’t enter an amount on line 18 unless you need to credit for qualified sick and family leave compensation for
correct any current year adjustments reported on Form leave taken after March 31, 2020, and before April 1,
CT-1, line 14. However, if you need to correct sick pay 2021, that you reported on Form CT-1, line 16, enter the
adjustments for prior years reported on Form CT-1, total corrected amount from Worksheet 1, Step 2, line 2j,
line 14, include the corrections in the calculations of Form in column 1. In column 2, enter the amount you originally
CT-1 X, lines 13–17. reported or as previously corrected. In column 3, enter the
Enter the corrected amount for tax adjustments in difference between columns 1 and 2. For more information
column 1. Enter the originally reported or previously about the credit for qualified sick and family leave
corrected current year amount from Form CT-1, line 14, in compensation, go to IRS.gov/PLC.
column 2. In column 3, enter the difference between Copy the amount in column 3 to column 4. However, to
columns 1 and 2. properly show the amount as a credit or balance due item,
enter a positive number in column 3 as a negative number
line 18 (column 1) in column 4 or a negative number in column 3 as a
- line 18 (column 2) positive number in column 4.
line 18 (column 3)
Instructions for Form CT-1 X (Rev. 4-2025) 13
Adjustments to the nonrefundable portion of the Column 1 Column 2 Column 3 Column 4
TIP credit for qualified sick and family leave (corrected (Form CT-1, (difference) (tax correction)
compensation for leave taken after March 31, amount) line 16)
2020, and before April 1, 2021, are reported on Form CT-1 2,000.00 1,000.00 1,000.00 -1,000.00
X, line 19, and adjustments to the refundable portion of
the credit are reported on Form CT-1 X, line 24.
Adjustments to qualified sick leave compensation and Be sure to explain the reasons for this correction on
qualified family leave compensation for leave taken after line 43.
March 31, 2020, and before April 1, 2021, are reported on
Form CT-1 X, lines 27 and 29, respectively. Adjustments 20b. Nonrefundable Portion of Credit for
to qualified health plan expenses allocable to qualified Qualified Sick and Family Leave Compensation
sick leave compensation and qualified family leave
compensation for leave taken after March 31, 2020, and
for Leave Taken After March 31, 2021, and
before April 1, 2021, are reported on Form CT-1 X, lines Before October 1, 2021
28 and 30, respectively. For corrections to 2020 Form Generally, the period of limitations for correcting
CT-1, line 16, if the period of limitations is still open, the the nonrefundable portion of credit for qualified
credit for qualified sick and family leave compensation is
!
CAUTION sick and family leave compensation paid in 2021
only available for compensation paid with respect to leave expired on February 28, 2025, for most employers. For
taken after March 31, 2020, and before January 1, 2021. more information about the period of limitations, see Is
For corrections to 2021, 2022, or 2023 Form CT-1, line 16, There a Deadline for Filing Form CT-1 X, earlier.
the credit for qualified sick and family leave compensation
is only available for compensation paid in 2021, 2022, or If you’re correcting the nonrefundable portion of the
2023 with respect to any leave taken after March 31, credit for qualified sick and family leave compensation for
2020, and before April 1, 2021. If you're correcting a year leave taken after March 31, 2021, and before October 1,
before 2020 because the period of limitations is still open, 2021, that you reported on Form CT-1, line 17b, enter the
don't enter any amount on line 19. If you claimed the credit total corrected amount from Worksheet 2, Step 2, line 2r,
for qualified sick and family leave compensation for leave in column 1. In column 2, enter the amount you originally
taken after March 31, 2020, and before April 1, 2021, on reported or as previously corrected. In column 3, enter the
your original Form CT-1, and you make any corrections on difference between columns 1 and 2. For more information
Form CT-1 X for the year to amounts used to figure this about the credit for qualified sick and family leave
credit, you’ll need to refigure the amount of the credit compensation, go to IRS.gov/PLC.
using Worksheet 1. You’ll also use this worksheet to figure For corrections to 2021, 2022, or 2023 Form CT-1,
this credit if you’re claiming the credit for the first time on line 17b, the credit for qualified sick and family leave
Form CT-1 X. For more information about the credit for compensation is only available for compensation paid in
qualified sick and family leave compensation, go to 2021, 2022, or 2023 with respect to leave taken after
IRS.gov/PLC. March 31, 2021, and before October 1, 2021. If you're
correcting a year before 2021 because the period of
Example—Nonrefundable portion of credit for limitations is still open, don't enter any amount on line 20b.
qualified sick and family leave compensation
increased. You originally reported a $1,000 Copy the amount in column 3 to column 4. However, to
nonrefundable portion of credit for qualified sick and properly show the amount as a credit or balance due item,
family leave compensation on your 2021 Form CT-1, enter a positive number in column 3 as a negative number
line 16, but later determined that you understated qualified in column 4 or a negative number in column 3 as a
sick leave compensation eligible for the credit. If your positive number in column 4. For an example of how to
period of limitations is still open, use Worksheet 1 to report amounts in columns 1–4 for an employment tax
refigure the correct nonrefundable portion of the credit for credit, see the instructions for line 19, earlier.
qualified sick and family leave compensation and you Be sure to explain the reasons for this correction on
determine that the correct credit is now $2,000. To correct line 43.
the error, figure the difference on Form CT-1 X as shown.
20c. Nonrefundable Portion of COBRA Premium
Column 1 (corrected amount) 2,000.00 Assistance Credit
Column 2 (Form CT-1, line 16) - 1,000.00
COBRA premium assistance was available for periods of
Column 3 (difference) 1,000.00 coverage beginning on or after April 1, 2021, through
periods of coverage beginning on or before September
30, 2021. For more information, see Credit for COBRA
To properly show the credit increase as a reduction to premium assistance payments is limited to periods of
your balance, enter the positive number in column 3 as a coverage beginning on or after April 1, 2021, through
negative number in column 4. Here is how you would periods of coverage beginning on or before September
enter the numbers on Form CT-1 X, line 19. 30, 2021 under Reminders, earlier.
14 Instructions for Form CT-1 X (Rev. 4-2025)
Premium payees that receive an election from an 2025, for most employers. For more information about the
TIP assistance eligible individual are entitled to the period of limitations, see Is There a Deadline for Filing
COBRA premium assistance credit for premiums Form CT-1 X, earlier.
not paid during the quarter in which the election is If you’re correcting the refundable portion of the credit
received. See Notice 2021-31 for more information.
for qualified sick and family leave compensation for leave
taken after March 31, 2020, and before April 1, 2021, that
If you’re correcting the nonrefundable portion of the you reported on Form CT-1, line 23, enter the total
COBRA premium assistance credit that you reported on corrected amount from Worksheet 1, Step 2, line 2k, in
Form CT-1, line 17c, enter the total corrected amount from column 1. In column 2, enter the amount you originally
Worksheet 3, Step 2, line 2g, in column 1. In column 2, reported or as previously corrected. In column 3, enter the
enter the amount you originally reported or as previously difference between columns 1 and 2. For more information
corrected. In column 3, enter the difference between about the credit for qualified sick and family leave
columns 1 and 2. compensation, go to IRS.gov/PLC.
Copy the amount in column 3 to column 4. However, to For corrections to 2020 Form CT-1, line 23, if the period
properly show the amount as a credit or balance due item, of limitations is still open, the credit for qualified sick and
enter a positive number in column 3 as a negative number family leave compensation is only available for
in column 4 or a negative number in column 3 as a compensation paid with respect to leave taken after March
positive number in column 4. For an example of how to 31, 2020, and before January 1, 2021. For corrections to
report amounts in columns 1–4 for an employment tax 2021, 2022, or 2023 Form CT-1, line 23, the credit for
credit, see the instructions for line 19, earlier. qualified sick and family leave compensation is only
Be sure to explain the reasons for this correction on available for compensation paid in 2021, 2022, or 2023
line 43. with respect to any leave taken after March 31, 2020, and
before April 1, 2021. If you're correcting a year before
20d. Number of Individuals Provided COBRA 2020 because the period of limitations is still open, don't
Premium Assistance enter any amount on line 24.
If you’re correcting the number of individuals provided Copy the amount in column 3 to column 4. However, to
COBRA premium assistance that you reported on Form properly show the amount as a credit or balance due item,
CT-1, line 17d, enter the total corrected amount in column enter a positive number in column 3 as a negative number
1. In column 2, enter the amount you originally reported or in column 4 or a negative number in column 3 as a
as previously corrected. In column 3, enter the difference positive number in column 4. For an example of how to
between columns 1 and 2. report amounts in columns 1–4 for an employment tax
credit, see the instructions for line 19, earlier.
Be sure to explain the reasons for this correction on
line 43. Be sure to explain the reasons for this correction on
line 43.
21. Subtotal
Combine the amounts from column 4 on lines 6–20c and 25b. Refundable Portion of Credit for Qualified
enter the result on line 21. Sick and Family Leave Compensation for Leave
Example. You entered “-500.00” in column 4 of line 6, Taken After March 31, 2021, and Before October
“-100.00” in column 4 of line 7, and “1,400.00” in column 4 1, 2021
of line 18. Combine these amounts and enter “800.00” in Generally, the period of limitations for correcting
column 4 of line 21. the refundable portion of credit for qualified sick
!
CAUTION and family leave compensation paid in 2021
Line 6 -500.00 expired on February 28, 2025, for most employers. For
Line 7 -100.00 more information about the period of limitations, see Is
Line 18 + 1,400.00 There a Deadline for Filing Form CT-1 X, earlier.
Line 21 800.00
If you’re correcting the refundable portion of the credit
for qualified sick and family leave compensation for leave
taken after March 31, 2021, and before October 1, 2021,
that you reported on Form CT-1, line 24b, enter the total
24. Refundable Portion of Credit for Qualified corrected amount from Worksheet 2, Step 2, line 2s, in
Sick and Family Leave Compensation for Leave column 1. In column 2, enter the amount you originally
Taken After March 31, 2020, and Before April 1, reported or as previously corrected. In column 3, enter the
2021 difference between columns 1 and 2. For more information
about the credit for qualified sick and family leave
Generally, the period of limitations for correcting
compensation, go to IRS.gov/PLC.
! the refundable portion of credit for qualified sick
CAUTION and family leave compensation paid in 2020 For corrections to 2021, 2022, or 2023 Form CT-1,
expired on February 29, 2024, for most employers. line 24b, the credit for qualified sick and family leave
Generally, the period of limitations for correcting the compensation is only available for compensation paid in
refundable portion of credit for qualified sick and family 2021, 2022, or 2023 with respect to leave taken after
leave compensation paid in 2021 expired on February 28, March 31, 2021, and before October 1, 2021. If you're
Instructions for Form CT-1 X (Rev. 4-2025) 15
correcting a year before 2021 because the period of Amount you owe. If the amount entered on line 26 is a
limitations is still open, don't enter any amount on line 25b. positive number, you must pay the amount you owe by
the time you file Form CT-1 X. You may not use any
Copy the amount in column 3 to column 4. However, to
credit that you show on another Form CT-1 X to pay the
properly show the amount as a credit or balance due item,
amount you owe, even if you filed for the amount you owe
enter a positive number in column 3 as a negative number
and the credit at the same time.
in column 4 or a negative number in column 3 as a
positive number in column 4. For an example of how to If you owe tax and are filing a timely Form CT-1 X, don’t
report amounts in columns 1–4 for an employment tax file an amended Form 945-A unless you were assessed
credit, see the instructions for line 19, earlier. an FTD penalty caused by an incorrect, incomplete, or
missing Form 945-A. Don’t include the tax increase
Be sure to explain the reasons for this correction on reported on Form CT-1 X on any amended Form 945-A
line 43. you file.
If you owe tax and are filing a late Form CT-1 X, that is,
25c. Refundable Portion of COBRA Premium after the due date for Form CT-1 for the period in which
Assistance Credit you discovered the error, you must file an amended Form
COBRA premium assistance was available for periods of 945-A with the Form CT-1 X. Otherwise, the IRS may
coverage beginning on or after April 1, 2021, through assess an “averaged” FTD penalty. The total tax reported
periods of coverage beginning on or before September on Form 945-A, line M, must match the corrected tax
30, 2021. For more information, see Credit for COBRA (Form CT-1, line 15 (line 19 for tax years 2020–2023),
premium assistance payments is limited to periods of combined with any correction reported on Form CT-1 X,
coverage beginning on or after April 1, 2021, through line 21) for the year, less any previous abatements and
periods of coverage beginning on or before September interest-free tax assessments.
30, 2021 under Reminders, earlier. Payment methods. You may pay the amount you owe
on line 26 electronically using the Electronic Federal Tax
If you’re correcting the refundable portion of the Payment System (EFTPS) or by a check or money order.
COBRA premium assistance credit that you reported on • The preferred method of payment is EFTPS. For more
Form CT-1, line 24c, enter the total corrected amount from information, go to EFTPS.gov or call 800-555-4477. To
Worksheet 3, Step 2, line 2h, in column 1. In column 2, contact EFTPS using Telecommunications Relay Services
enter the amount you originally reported or as previously (TRS) for people who are deaf, hard of hearing, or have a
corrected. In column 3, enter the difference between speech disability, dial 711 and then provide the TRS
columns 1 and 2. assistant the 800-555-4477 number above or
Copy the amount in column 3 to column 4. However, to 800-733-4829. Additional information about EFTPS is also
properly show the amount as a credit or balance due item, available in Pub. 966.
enter a positive number in column 3 as a negative number • If you pay by check or money order, make it payable to
in column 4 or a negative number in column 3 as a “United States Treasury.” On your check or money order,
positive number in column 4. For an example of how to be sure to write your EIN, “Form CT-1 X,” and the year
report amounts in columns 1–4 for an employment tax corrected.
credit, see the instructions for line 19, earlier. You don’t have to pay if the amount you owe is less than
$1.
Be sure to explain the reasons for this correction on
line 43. Lines 27–30 and 33–38
For lines 27–30 and 33–38, you’ll only enter amounts in
26. Total columns 1, 2, and 3. These lines don’t have an entry
Combine the amounts from column 4 on lines 21–25c and space for column 4 because these adjustments don’t
enter the result on line 26. directly result in an increase or decrease to your tax. The
Your credit. If the amount entered on line 26 is less than amounts entered on lines 27–30 and 33–38 are amounts
zero, for example, “-115.00,” you have a credit because that you use on Worksheets 1–3, as applicable, to figure
you overreported your RRTA taxes. your credits. If you reported an incorrect amount on lines
• If you checked the box on line 1, include this amount on 30–33 and 36–41 on your original Form CT-1, then you’ll
Form CT-1, line 16 (“Total railroad retirement tax use lines 27–30 and 33–38 of Form CT-1 X to report the
deposits”), for the year during which you filed Form CT-1 correction. You’ll also use these lines to report amounts if
X. Don’t make any changes to your Record of Railroad you’re claiming any credits for the first time on Form CT-1
Retirement Tax Liability in Part II of Form CT-1 or on Form X. Use Worksheets 1–3, as applicable, to refigure your
945-A, unless you were assessed an FTD penalty. For credits based on the corrected amounts reported in
more information, see the Instructions for Form 945-A. column 1. Be sure to explain the reasons for your
The amounts reported on the record should reflect your corrections to lines 27–30 and 33–38 on line 43.
actual tax liability for the period.
• If you checked the box on line 2, you’re filing a claim for
refund or abatement of the amount shown.
If your credit is less than $1, we will send a refund or
apply it to your next return only if you ask us in writing to
do so.
16 Instructions for Form CT-1 X (Rev. 4-2025)
27. Qualified Sick Leave Compensation for 29. Qualified Family Leave Compensation for
Leave Taken After March 31, 2020, and Before Leave Taken After March 31, 2020, and Before
April 1, 2021 April 1, 2021
Generally, the period of limitations for correcting Generally, the period of limitations for correcting
! qualified sick leave compensation paid in 2020 ! qualified family leave compensation paid in 2020
CAUTION expired on February 29, 2024, for most CAUTION expired on February 29, 2024, for most
employers. Generally, the period of limitations for employers. Generally, the period of limitations for
correcting qualified sick leave compensation paid in 2021 correcting qualified family leave compensation paid in
expired on February 28, 2025, for most employers. For 2021 expired on February 28 2025, for most employers.
more information about the period of limitations, see Is For more information about the period of limitations, see Is
There a Deadline for Filing Form CT-1 X, earlier. There a Deadline for Filing Form CT-1 X, earlier.
If you’re correcting the qualified sick leave If you’re correcting the qualified family leave
compensation for leave taken after March 31, 2020, and compensation for leave taken after March 31, 2020, and
before April 1, 2021, that you reported on Form CT-1, before April 1, 2021, you reported on Form CT-1, line 32,
line 30, enter the total corrected amount for all employees enter the total corrected amount for all employees in
in column 1. In column 2, enter the amount you originally column 1. In column 2, enter the amount you originally
reported or as previously corrected. In column 3, enter the reported or as previously corrected. In column 3, enter the
difference between columns 1 and 2. Qualified sick leave difference between columns 1 and 2. Qualified family
compensation reported on this line is compensation leave compensation reported on this line is compensation
(determined without regard to the exclusions under (determined without regard to the exclusions under
section 3231(e)(1)) paid under the Emergency Paid Sick section 3231(e)(1)) paid under the Emergency Family and
Leave Act (EPSLA) as enacted under the FFCRA and as Medical Leave Expansion Act (Expanded FMLA) as
amended by the COVID-related Tax Relief Act of 2020. enacted under the FFCRA and as amended by the
Enter the corrected amount from column 1 on Worksheet COVID-related Tax Relief Act of 2020. Enter the corrected
1, Step 2, line 2a. amount from column 1 on Worksheet 1, Step 2, line 2e.
Be sure to explain the reasons for this correction on Be sure to explain the reasons for this correction on
line 43. line 43.
28. Qualified Health Plan Expenses Allocable to 30. Qualified Health Plan Expenses Allocable to
Qualified Sick Leave Compensation for Leave Qualified Family Leave Compensation for Leave
Taken After March 31, 2020, and Before April 1, Taken After March 31, 2020, and Before April 1,
2021 2021
Generally, the period of limitations for correcting Generally, the period of limitations for correcting
! qualified health plan expenses allocable to ! qualified health plan expenses allocable to
CAUTION qualified sick leave compensation paid in 2020 CAUTION qualified family leave compensation paid in 2020
expired on February 29, 2024, for most employers. expired on February 29, 2024, for most employers.
Generally, the period of limitations for correcting qualified Generally, the period of limitations for correcting qualified
health plan expenses allocable to qualified sick leave health plan expenses allocable to qualified family leave
compensation paid in 2021 expired on February 28, 2025, compensation paid in 2021 expired on February 28, 2025,
for most employers. For more information about the period for most employers. For more information about the period
of limitations, see Is There a Deadline for Filing Form CT-1 of limitations, see Is There a Deadline for Filing Form CT-1
X, earlier. X, earlier.
If you’re correcting the qualified health plan expenses If you’re correcting the qualified health plan expenses
allocable to qualified sick leave compensation for leave allocable to qualified family leave compensation for leave
taken after March 31, 2020, and before April 1, 2021, that taken after March 31, 2020, and before April 1, 2021, that
you reported on Form CT-1, line 31, enter the total you reported on Form CT-1, line 33, enter the total
corrected amount for all employees in column 1. In column corrected amount for all employees in column 1. In column
2, enter the amount you originally reported or as 2, enter the amount you originally reported or as
previously corrected. In column 3, enter the difference previously corrected. In column 3, enter the difference
between columns 1 and 2. Enter the corrected amount between columns 1 and 2. Enter the corrected amount
from column 1 on Worksheet 1, Step 2, line 2b. from column 1 on Worksheet 1, Step 2, line 2f.
Be sure to explain the reasons for this correction on Be sure to explain the reasons for this correction on
line 43. line 43.
Instructions for Form CT-1 X (Rev. 4-2025) 17
33. Qualified Sick Leave Compensation for If you’re correcting the amounts under certain
Leave Taken After March 31, 2021, and Before collectively bargained agreements allocable to qualified
October 1, 2021 sick leave compensation for leave taken after March 31,
2021, and before October 1, 2021, that you reported on
Generally, the period of limitations for correcting Form CT-1, line 38, enter the total corrected amount for all
! qualified sick leave compensation paid in 2021 employees in column 1. In column 2, enter the amount you
CAUTION expired on February 28, 2025, for most originally reported or as previously corrected. In column 3,
employers. For more information about the period of enter the difference between columns 1 and 2. Enter the
limitations, see Is There a Deadline for Filing Form CT-1 X, corrected amount from column 1 on Worksheet 2, Step 2,
earlier. line 2c.
If you’re correcting the qualified sick leave Be sure to explain the reasons for this correction on
compensation for leave taken after March 31, 2021, and line 43.
before October 1, 2021, that you reported on Form CT-1,
line 36, enter the total corrected amount in column 1. In 36. Qualified Family Leave Compensation for
column 2, enter the amount you originally reported or as Leave Taken After March 31, 2021, and Before
previously corrected. In column 3, enter the difference
between columns 1 and 2. Qualified sick leave October 1, 2021
compensation reported on this line is compensation Generally, the period of limitations for correcting
(determined without regard to the exclusions under ! qualified family leave compensation paid in 2021
section 3231(e)(1)) paid under the EPSLA as enacted CAUTION expired on February 28, 2025, for most
under the FFCRA and amended for purposes of the ARP. employers. For more information about the period of
Enter the corrected amount from column 1 on Worksheet limitations, see Is There a Deadline for Filing Form CT-1 X,
2, Step 2, line 2a. earlier.
Be sure to explain the reasons for this correction on If you’re correcting the qualified family leave
line 43. compensation for leave taken after March 31, 2021, and
before October 1, 2021, that you reported on Form CT-1,
34. Qualified Health Plan Expenses Allocable to line 39, enter the total corrected amount in column 1. In
Qualified Sick Leave Compensation for Leave column 2, enter the amount you originally reported or as
Taken After March 31, 2021, and Before October previously corrected. In column 3, enter the difference
between columns 1 and 2. Qualified family leave
1, 2021 compensation reported on this line is compensation
Generally, the period of limitations for correcting (determined without regard to the exclusions under
! qualified health plan expenses allocable to section 3231(e)(1)) paid under the Expanded FMLA as
CAUTION qualified sick leave compensation paid in 2021 enacted under the FFCRA and amended for purposes of
expired on February 28, 2025, for most employers. For the ARP. Enter the corrected amount from column 1 on
more information about the period of limitations, see Is Worksheet 2, Step 2, line 2g.
There a Deadline for Filing Form CT-1 X, earlier.
Be sure to explain the reasons for this correction on
If you’re correcting the qualified health plan expenses line 43.
allocable to qualified sick leave compensation for leave
taken after March 31, 2021, and before October 1, 2021, 37. Qualified Health Plan Expenses Allocable to
that you reported on Form CT-1, line 37, enter the total Qualified Family Leave Compensation for Leave
corrected amount for all employees in column 1. In column Taken After March 31, 2021, and Before October
2, enter the amount you originally reported or as
previously corrected. In column 3, enter the difference 1, 2021
between columns 1 and 2. Enter the corrected amount Generally, the period of limitations for correcting
from column 1 on Worksheet 2, Step 2, line 2b. ! qualified health plan expenses allocable to
CAUTION qualified family leave compensation paid in 2021
Be sure to explain the reasons for this correction on expired on February 28, 2025, for most employers. For
line 43. more information about the period of limitations, see Is
There a Deadline for Filing Form CT-1 X, earlier.
35. Amounts Under Certain Collectively
Bargained Agreements Allocable to Qualified If you’re correcting the qualified health plan expenses
Sick Leave Compensation for Leave Taken After allocable to qualified family leave compensation for leave
taken after March 31, 2021, and before October 1, 2021,
March 31, 2021, and Before October 1, 2021 that you reported on Form CT-1, line 40, enter the total
Generally, the period of limitations for correcting corrected amount for all employees in column 1. In column
! the amounts under certain collectively bargained 2, enter the amount you originally reported or as
CAUTION agreements allocable to qualified sick leave previously corrected. In column 3, enter the difference
compensation paid in 2021 expired on February 28, 2025, between columns 1 and 2. Enter the corrected amount
for most employers. For more information about the period from column 1 on Worksheet 2, Step 2, line 2h.
of limitations, see Is There a Deadline for Filing Form CT-1
X, earlier. Be sure to explain the reasons for this correction on
line 43.
18 Instructions for Form CT-1 X (Rev. 4-2025)
38. Amounts Under Certain Collectively top of Form CT-1 X, including the date you discovered the
Bargained Agreements Allocable to Qualified error, and provide a detailed explanation on line 43.
Family Leave Compensation for Leave Taken 43. Explain Your Corrections
After March 31, 2021, and Before October 1, Treasury regulations require you to explain in detail the
2021 grounds and facts relied upon to support each correction.
Generally, the period of limitations for correcting On line 43, describe in detail each correction you entered
the amounts under certain collectively bargained in column 4 on lines 6–19, 20b–20d, 24, 25b, and 25c.
!
CAUTION agreements allocable to qualified family leave Also use line 43 to describe corrections made on lines 27–
compensation paid in 2021 expired on February 28, 2025, 30 and 33–38. If you need more space, attach additional
for most employers. For more information about the period sheets, but be sure to write your name, EIN, “Form CT-1
of limitations, see Is There a Deadline for Filing Form CT-1 X,” and the calendar year you’re correcting on the top of
X, earlier. each sheet.
If you’re correcting the amounts under certain You must describe the events that caused the
collectively bargained agreements allocable to qualified underreported or overreported amounts. Explanations
family leave compensation for leave taken after March 31, such as “RRTA compensation was overstated,”
2021, and before October 1, 2021, that you reported on “administrative/payroll errors were discovered,” or “taxes
Form CT-1, line 41, enter the total corrected amount for all were not withheld” are insufficient and may delay the
employees in column 1. In column 2, enter the amount you processing of your Form CT-1 X because the IRS may
originally reported or as previously corrected. In column 3, need to ask for a more complete explanation.
enter the difference between columns 1 and 2. Enter the Provide the following information in your explanation of
corrected amount from column 1 on Worksheet 2, Step 2, each correction.
line 2i. • Form CT-1 X line number(s) affected.
Be sure to explain the reasons for this correction on • Date you discovered the error.
line 43. • Difference (amount of the error).
• Cause of the error.
Part 4: Explain Your Corrections for You may report the information in paragraph form. The
following paragraph is an example.
the Calendar Year You’re Correcting
“The $1,000 difference shown in column 3 of lines 6
41. Corrections of Both Underreported and and 7 was discovered on May 15, 2025, during an internal
Overreported Amounts payroll audit. We discovered that we included $1,000 of
compensation for one of our employees twice. This
Check the box on line 41 if any corrections you entered on correction removes the reported compensation that was
lines 6–19, 20b–20d, 24, 25b, 25c, 27–30, or 33–38 in never paid.”
column 3 reflect both underreported and overreported
amounts. Part 5: Sign Here
Example. If you had an increase to Tier 1 Employer You must complete all five pages of Form CT-1 X and sign
compensation of $15,000 for Nathan Smith and a it on page 5. If you don’t sign, the processing of Form
decrease to Tier 1 Employer compensation of $5,000 for CT-1 X will be delayed.
Leah Green, you would enter $10,000 on line 6, column 3.
That $10,000 represents the net change resulting from Who must sign Form CT-1 X? The following persons
corrections. are authorized to sign the return for each type of business
On line 43, you must explain the reasons for both the entity.
$15,000 increase and the $5,000 decrease. • Sole proprietorship—The individual who owns the
business.
42. Did You Reclassify Any Workers? • Corporation (including a limited liability company
Check the box on line 42 if you reclassified any workers to (LLC) treated as a corporation)—The president, the
be independent contractors or nonemployees. Also check vice president, or other principal officer duly authorized to
this box if the IRS (or you) determined that workers you sign.
treated as independent contractors or nonemployees • Partnership (including an LLC treated as a
should be classified as employees. On line 43, provide a partnership) or unincorporated organization—A
detailed reason why any worker was reclassified. responsible and duly authorized partner, member, or
officer having knowledge of its affairs.
Return not filed because you didn’t treat any workers • Single-member LLC treated as a disregarded entity
as employees. If you didn’t previously file Form CT-1 for federal income tax purposes—The owner of the
because you mistakenly treated all workers as LLC or a principal officer duly authorized to sign.
independent contractors or nonemployees, file a Form • Trust or estate—The fiduciary.
CT-1 for each delinquent year. A duly authorized agent of the taxpayer may also sign
Write “Misclassified Employees” in bold letters Form CT-1 X if a valid power of attorney has been filed.
across the top margin of page 1 of each Form CT-1.
Complete Form CT-1 using the Instructions for Form CT-1. Alternative signature method. Corporate officers or
Attach a Form CT-1 X to each Form CT-1. Complete the duly authorized agents may sign Form CT-1 X by rubber
stamp, mechanical device, or computer software program.
Instructions for Form CT-1 X (Rev. 4-2025) 19
For details and required documentation, see Rev. Proc.
Paperwork Reduction Act Notice. We ask for the
2005-39, 2005-28 I.R.B. 82, available at IRS.gov/irb/
information on Form CT-1 X to carry out the Internal
2005-28_IRB#RP-2005-39.
Revenue laws of the United States. You’re required to give
Paid Preparer Use Only us the information. We need it to ensure that you’re
complying with these laws and to allow us to figure and
A paid preparer must sign Form CT-1 X and provide the
collect the right amount of tax.
information in the Paid Preparer Use Only section of Part 5
if the preparer was paid to prepare Form CT-1 X and isn’t You're not required to provide the information requested
an employee of the filing entity. Paid preparers must sign on a form that is subject to the Paperwork Reduction Act
paper returns with a manual signature. The preparer must unless the form displays a valid OMB control number.
give the employer the return to file with the IRS and Books or records relating to a form or its instructions must
include a copy of the return for the employer's records. be retained as long as their contents may become
If you’re a paid preparer, write your Preparer Tax material in the administration of any Internal Revenue law.
Identification Number (PTIN) in the space provided. Generally, tax returns and return information are
Include your complete address. If you work for a firm, write confidential, as required by section 6103.
the firm's name and the EIN of the firm. You can apply for The time needed to complete and file Form CT-1 X will
a PTIN online or by filing Form W-12. For more information vary depending on individual circumstances. The
about applying for a PTIN online, go to IRS.gov/PTIN. You estimated burden for employers filing Form CT-1 X is
can’t use your PTIN in place of the EIN of the tax approved under OMB control number 1545-0029 and is
preparation firm. included in the estimates shown in the Instructions for
Generally, you’re not required to complete this section if Form 941.
you’re filing the return as a reporting agent and have a
valid Form 8655 on file with the IRS. However, a reporting
agent must complete this section if the reporting agent
offered legal advice, for example, advising the client on
determining whether its workers are employees or
independent contractors for federal tax purposes.
How Can You Get Forms, Instructions,
and Publications From the IRS?
You can download or print some of the forms and
publications you may need at IRS.gov/Forms.
Otherwise, you can go to IRS.gov/OrderForms to
place an order and have forms mailed to you. The IRS will
process your order for forms and publications as soon as
possible. Don’t resubmit requests you’ve already sent us.
You can get forms and publications faster online.
20 Instructions for Form CT-1 X (Rev. 4-2025)
Worksheet 1. Adjusted Credit for Qualified Sick and Family Leave
Compensation for Leave Taken After March 31, 2020, and Before
April 1, 2021 Keep for Your Records
You must use this worksheet if you claimed the credit for qualified sick and family leave compensation for leave taken after March 31, 2020, and
before April 1, 2021, on your original Form CT-1 and you correct any amounts used to figure the credit for qualified sick and family leave
compensation for leave taken after March 31, 2020, and before April 1, 2021. You'll also use this worksheet to figure this credit if you're claiming it
for the first time on Form CT-1 X.
Step 1. Figure the Tier 1 Employer Tax
1a Enter the amount from Form CT-1, line 1 (Tax Column), or, if corrected, enter the
amount from Form CT-1 X, line 6, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1a
1b Enter the amount from Form CT-1, line 8 (Tax Column), or, if corrected, enter the
amount from Form CT-1 X, line 13, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1b
1c Tier 1 Employer tax. Add lines 1a and 1b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1c
Step 2. Figure the credit for qualified sick and family leave compensation
2a Qualified sick leave compensation reported on Form CT-1, line 30, or, if corrected, the
amount from Form CT-1 X, line 27, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a
2a(i) Enter the amount, if any, included on line 2a that is compensation excluded from the
definition of compensation under section 3231(e)(1) . . . . . . . . . . . . . . . . . . . . . . . . . 2a(i)
2a(ii) Subtract line 2a(i) from line 2a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a(ii)
2b Qualified health plan expenses allocable to qualified sick leave compensation reported
on Form CT-1, line 31, or, if corrected, Form CT-1 X, line 28, column 1 . . . . . . . . . . . . 2b
2c Tier 1 Employer Medicare tax on qualified sick leave compensation. Multiply line 2a(ii)
by 1.45% (0.0145) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2c
2d Credit for qualified sick leave compensation. Add lines 2a, 2b, and 2c . . . . . . . . . 2d
2e Qualified family leave compensation reported on Form CT-1, line 32, or, if corrected,
the amount from Form CT-1 X, line 29, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2e
2e(i) Enter the amount, if any, included on line 2e that is compensation excluded from the 2e(i)
definition of compensation under section 3231(e)(1) . . . . . . . . . . . . . . . . . . . . . . . . .
2e(ii) Subtract line 2e(i) from line 2e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2e(ii)
2f Qualified health plan expenses allocable to qualified family leave compensation
reported on Form CT-1, line 33, or, if corrected, the amount from Form CT-1 X, line 30,
column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2f
2g Tier 1 Employer Medicare tax on qualified family leave compensation. Multiply
line 2e(ii) by 1.45% (0.0145) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2g
2h Credit for qualified family leave compensation. Add lines 2e, 2f, and 2g . . . . . . . 2h
2i Credit for qualified sick and family leave compensation. Add lines 2d
and 2h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2i
2j Nonrefundable portion of credit for qualified sick and family leave
compensation for leave taken after March 31, 2020, and before April 1, 2021.
Enter the smaller of line 1c or line 2i. Enter this amount on Form CT-1 X, line 19,
column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2j
2k Refundable portion of credit for qualified sick and family leave compensation
for leave taken after March 31, 2020, and before April 1, 2021. Subtract line 2j
from line 2i and enter this amount on Form CT-1 X, line 24, column 1 . . . . . . . . . . . . . 2k
Instructions for Form CT-1 X (Rev. 4-2025) 21
Worksheet 2. Adjusted Credit for Qualified Sick and Family Leave
Compensation for Leave Taken After March 31, 2021, and Before
October 1, 2021 Keep for Your Records
You must use this worksheet if you claimed the credit for qualified sick and family leave compensation for leave taken after March 31, 2021, and before
October 1, 2021, on your original Form CT-1 and you correct any amounts used to figure the credit for qualified sick and family leave compensation for leave
taken after March 31, 2021, and before October 1, 2021. You'll also use this worksheet to figure this credit if you're claiming it for the first time on Form CT-1 X.
Step 1. Figure the Tier 1 Employer Medicare Tax
1a Enter the amount from Form CT-1, line 2 (Tax Column), or, if corrected, the amount from Form
CT-1 X, line 7, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1a
1b Enter the amount from Form CT-1, line 9 (Tax Column), or, if corrected, the amount from Form
CT-1 X, line 14, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1b
1c Tier 1 Employer Medicare tax. Add lines 1a and 1b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1c
Step 2. Figure the credit for qualified sick and family leave compensation
2a Qualified sick leave compensation for leave taken after March 31, 2021, and before October 1,
2021, reported on Form CT-1, line 36, or, if corrected, the amount from Form CT-1 X, line 33,
column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a
2a(i) Enter the amount, if any, included on line 2a that is compensation excluded from the definition
of compensation under section 3231(e)(1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a(i)
2a(ii) Subtract line 2a(i) from line 2a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a(ii)
2a(iii) Enter the amount, if any, included on line 2a that was not included as compensation on Form
CT-1, lines 1, 4, 8, and 10, or, if corrected, on Form CT-1 X, lines 6, 9, 13, and 15, because the
qualified sick leave compensation was limited by the Tier 1 compensation base . . . . . . . . . . . 2a(iii)
2a(iv) Subtract line 2a(iii) from line 2a(ii) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a(iv)
2b Qualified health plan expenses allocable to qualified sick leave compensation taken after March
31, 2021, and before October 1, 2021, reported on Form CT-1, line 37, or, if corrected, the
amount from Form CT-1 X, line 34, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2b
2c Amounts under certain collectively bargained agreements allocable to qualified sick leave
compensation for leave taken after March 31, 2021, and before October 1, 2021, reported on
Form CT-1, line 38, or, if corrected, the amount from Form CT-1 X, line 35, column 1 . . . . . . . 2c
2d Tier 1 Employer tax on qualified sick leave compensation. Multiply line 2a(iv) by 6.2%
(0.062) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2d
2e Tier 1 Employer Medicare tax on qualified sick leave compensation. Multiply line 2a(ii) by 1.45%
(0.0145) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2e
2f Credit for qualified sick leave compensation. Add lines 2a, 2b, 2c, 2d, and 2e . . . . . . . . . 2f
2g Qualified family leave compensation for leave taken after March 31, 2021, and before October
1, 2021, reported on Form CT-1, line 39, or, if corrected, the amount from Form CT-1 X, line 36,
column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2g
2g(i) Enter the amount, if any, included on line 2g that is compensation excluded from the definition
of compensation under section 3231(e)(1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2g(i)
2g(ii) Subtract line 2g(i) from line 2g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2g(ii)
2g(iii) Enter the amount, if any, included on line 2g that was not included as compensation on Form
CT-1, lines 1, 4, 8, and 10, or, if corrected, on Form CT-1 X, lines 6, 9, 13, and 15, because the
qualified family leave compensation was limited by the Tier 1 compensation base . . . . . . . . . 2g(iii)
2g(iv) Subtract line 2g(iii) from line 2g(ii) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2g(iv)
2h Qualified health plan expenses allocable to qualified family leave compensation taken after
March 31, 2021, and before October 1, 2021, reported on Form CT-1, line 40, or, if corrected,
the amount from Form CT-1 X, line 37, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2h
2i Amounts under certain collectively bargained agreements allocable to qualified family leave
compensation for leave taken after March 31, 2021, and before October 1, 2021, reported on
Form CT-1, line 41, or, if corrected, the amount from Form CT-1 X, line 38, column 1 . . . . . . . 2i
2j Tier 1 Employer tax on qualified family leave compensation. Multiply line 2g(iv) by 6.2%
(0.062) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2j
2k Tier 1 Employer Medicare tax on qualified family leave compensation. Multiply line 2g(ii) by
1.45% (0.0145) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2k
2l Credit for qualified family leave compensation. Add lines 2g, 2h, 2i, 2j, and 2k . . . . . . . . . 2l
2m Credit for qualified sick and family leave compensation. Add lines 2f and 2l . . . . . . . . . . 2m
2n Reserved for future use
2o Enter any credit claimed under section 41 for increasing research activities with respect to any
compensation taken into account for the credit for qualified sick and family leave
compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2o
2p Reserved for future use
2q Credit for qualified sick and family leave compensation after adjusting for other credits.
Subtract line 2o from line 2m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2q
2r Nonrefundable portion of credit for qualified sick and family leave compensation for
leave taken after March 31, 2021, and before October 1, 2021. Enter the smaller of line 1c
or line 2q. Enter this amount on Form CT-1 X, line 20b, column 1 . . . . . . . . . . . . . . . . . . . . . 2r
2s Refundable portion of credit for qualified sick and family leave compensation for leave
taken after March 31, 2021, and before October 1, 2021. Subtract line 2r from line 2q and
enter this amount on Form CT-1 X, line 25b, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2s
22 Instructions for Form CT-1 X (Rev. 4-2025)
Worksheet 3. Adjusted COBRA Premium Assistance Credit Keep for Your Records
You must use this worksheet if you claimed the COBRA premium assistance credit on your original Form CT-1 and you correct any amounts used to figure the
COBRA premium assistance credit. You'll also use this worksheet to figure this credit if you're claiming it for the first time on Form CT-1 X.
Step 1. Figure the Tier 1 Employer Medicare Tax
1a If you completed Worksheet 2 and you’re also claiming the COBRA premium assistance credit,
enter the amount from Worksheet 2, Step 1, line 1c. Otherwise, complete lines 1b–1d below
and then go to Step 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1a
1b Enter the amount from Form CT-1, line 2 (Tax Column), or, if corrected, the amount from Form
CT-1 X, line 7, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1b
1c Enter the amount from Form CT-1, line 9 (Tax Column), or, if corrected, the amount from Form
CT-1 X, line 14, column 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1c
1d Tier 1 Employer Medicare tax. Add lines 1b and 1c . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1d
Step 2. Figure the COBRA premium assistance credit
2a Enter the COBRA premium assistance that you provided for periods of coverage beginning on
or after April 1, 2021, through periods of coverage beginning on or before September 30,
2021 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2a
2b Enter the amount of the Tier 1 Employer Medicare tax from Step 1, line 1a, or, if applicable,
Step 1, line 1d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2b
2c Enter the amount of the nonrefundable portion of the credit for qualified sick and family leave
compensation for leave taken after March 31, 2021, and before October 1, 2021 (this amount
may come from Worksheet 2, Step 2, line 2r, in these instructions if you're correcting that credit
or you may need to enter the credit claimed on your original Form CT-1) . . . . . . . . . . . . . . . 2c
2d Reserved for future use
2e Reserved for future use
2f Subtract line 2c from line 2b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2f
2g Nonrefundable portion of the COBRA premium assistance credit. Enter the smaller of
line 2a or line 2f. Enter this amount on Form CT-1 X, line 20c, column 1 . . . . . . . . . . . . . . . . 2g
2h Refundable portion of the COBRA premium assistance credit. Subtract line 2g from
line 2a and enter this amount on Form CT-1 X, line 25c, column 1 . . . . . . . . . . . . . . . . . . . 2h
Instructions for Form CT-1 X (Rev. 4-2025) 23
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