CT-1 X - Adjusted Employer's Annual Railroad Retirement Tax Return or Claim for Refund

Form

CT-1 X:

Adjusted Employer’s Annual Railroad Retirement Tax Return or Claim for Refund

(Rev. February 2014) 2015

Department of the Treasury — Internal Revenue Service

Employer identification number
(EIN)

OMB No. 1545-0001

Return You Are Correcting ...

—

Enter the calendar year of the return
you are correcting:

RRB number

(YYYY)
Name (as shown on latest Form CT-1)
Address
Number

Street

Suite or room number

City

separate

Foreign country name

State

Foreign province/county

completing

ZIP code

Enter the date you discovered errors:

(MM / DD / YYYY)

Foreign postal code

Read the instructions before you complete this form. Use this form to correct errors made on Form CT-1, Employer’s Annual Railroad
Retirement Tax Return. Use a separate Form CT-1 X for each year that needs correction. Type or print within the boxes. You MUST
complete all three pages. Do not attach this form to Form CT-1.
Part 1: Select ONLY one process. See page 4 for additional guidance.
1. Adjusted railroad retirement tax return. Check this box if you underreported amounts. Also check this box if you overreported amounts
and you would like to use the adjustment process to correct the errors. You must check this box if you are correcting both underreported
and overreported amounts on this form. The amount shown on line 20, if less than zero, may only be applied as a credit to your Form CT-1
for the tax period in which you are filing this form.
2. Claim. Check this box if you overreported amounts only and you would like to use the claim process to ask for a refund or abatement of the
amount shown on line 20. Do not check this box if you are correcting ANY underreported amounts on this form.

Part 2: Complete the certifications.
3. I certify that I have filed or will file Forms W-2, Wage and Tax Statement, or Forms W-2c, Corrected Wage and Tax Statement, as
1
required.
1
Note. If you are correcting underreported amounts only, go to Part 3 on page 2 and skip lines 4 and 5. If you are correcting overreported
amounts, for purposes of the certifications on lines 4 and 5, Employee Railroad Retirement Tax Act (RRTA) taxes consist of Tier I Employee
tax, Tier I Employee Medicare tax, and Tier II Employee tax. Employer RRTA taxes consist of Tier I Employer tax, Tier I Employer Medicare
tax, and Tier II Employer tax. Form CT-1 X cannot be used to correct overreported amounts of Tier I Employee Additional Medicare Tax unless
the amounts were not withheld from employee compensation. 2
1
2
4. If you checked line 1 because you are adjusting overreported amounts, check all that apply. You must check at least one box.
I certify that:
a. I repaid or reimbursed each affected employee for the overcollected RRTA taxes for prior years. I have a written statement from
each employee stating that he or she has not claimed (or the claim was rejected) and will not claim a refund or credit for the
overcollection.
b. The adjustments are only for Employer RRTA taxes. I could not find the affected employees or each employee did not give me a
written statement that he or she has not claimed (or the claim was rejected) and will not claim a refund or credit for the
overcollection.
c. The adjustment is for RRTA taxes and/or Tier I Employee Additional Medicare Tax that I did not withhold from employee compensation.
1
5. If you checked line 2 because you are claiming a refund or abatement of overreported RRTA taxes, check all that apply.
You must check at least one box.
I certify that:
a. I repaid or reimbursed each affected employee for the overcollected Employee RRTA taxes for prior years. I have a written statement
from each employee stating that he or she has not claimed (or the claim was rejected) and will not claim a refund or credit for the
overcollection.
b. I have a written consent from each affected employee stating that I may file this claim for Employee RRTA taxes overcollected in prior
years. I also have a written statement from each employee stating that he or she has not claimed (or the claim was rejected) and will
not claim a refund or credit for the overcollection.
c. The claim is for Employer RRTA taxes only. I could not find the affected employees; each employee did not give me a written consent
to file a claim for Employee RRTA taxes; or each employee did not give me a written statement that he or she has not claimed (or the
claim was rejected) and will not claim a refund or credit for the overcollection.
d. The claim is for RRTA taxes and/or Tier I Employee Additional Medicare Tax that I did not withhold from employee compensation.
1
Next Na
For Paperwork Reduction Act Notice, see the separate instructions.

IRS.gov/ct1x

Cat. No. 20338T

Form CT-1

X (Rev. 2-2014)
2015

Correcting
Name

Employer identification number (EIN)

Calendar Year (YYYY)

Part 3: Enter the corrections for the calendar year you are correcting. If any line does not apply, leave it blank.
Column 2

Column 1
Total corrected
amount (for ALL
employees)

—

Amount originally
reported or as
previously corrected
(for ALL employees)

Column 3

=

Column 4

Difference
(If this amount is a
negative number,
use a minus sign.)

Tax correction

6. 1 Tier I Employer Tax–
7. 1

Compensation
(Form CT-1, line 1)
Tier I Employer Medicare Tax–
Compensation
(Form CT-1, line 2)

.

—

.

.

—

.

.

—

.

.

—

.

=
=

=

× .062

.

× .0145 =

.

.

.

8.2 Tier II Employer Tax–
9.

1

1
10.
11.

1

Compensation
(Form CT-1, line 3)
Tier I Employee Tax–
Compensation
(Form CT-1, line 4)

=

See
instructions

.

=

.

× .062* =

.

.

*If you are correcting a 2011 or 2012 return, use .042.

Tier I Employee Medicare Tax–
Compensation
(Form CT-1, line 5)

.

—

.

Tier I Employee Additional
Medicare Tax–Compensation
(other than sick pay) (Form CT-1,
line 6; only for years beginning
after December 31, 2012)

.

—

.

=

× .0145 =

.

=

× .009 * =

.

.

.

*Certain compensation reported in Column 3 should not be multiplied by .009. See instructions.

12. 2 Tier II Employee Tax–

Compensation (Form CT-1, line 7
(line 6 for years ending before
January 1, 2013))

13.

—

.

(Form CT-1, line 8 (line 7 for years
ending before January 1, 2013))

.

—

.

Tier I Employer Medicare Tax–
Sick Pay (Form CT-1, line 9 (line 8
for years ending before January 1,
2013))

.

—

.

.

—

.

See
instructions

.

.

=

=

=

× .062

.

× .0145 =

.

.

.

1 Tier I Employee Tax–Sick Pay

(Form CT-1, line 10 (line 9 for years
ending before January 1, 2013))

16.

=

1 Tier I Employer Tax–Sick Pay

14.1

15.

.

=

18.

19.

Sick Pay (Form CT-1, line 11 (line
10 for years ending before January
1, 2013))

.

—

.

Tier I Employee Additional
Medicare Tax–Sick Pay (Form
CT-1, line 12; only for years
beginning after December 31, 2012)

.

—

.

Tax Adjustments (Form CT-1, line
14 (line 12 for years ending before
January 1, 2013))

.

*If you are correcting a 2011 or 2012 return, use .042.

1 Tier I Employee Medicare Tax–

17. 1

× .062* =

.

=

× .0145 =

.

=

× .009 * =

.

.

.

*Certain compensation reported in Column 3 should not be multiplied by .009. See instructions.

.

—

.

=

Total. Combine the amounts in lines 6 through 18 of Column 4. Continued on next page

.

.

.

.

.

.

See
instructions

.

.

.

.

.

Next Na
Page 2

Form CT-1

X (Rev. 2-2014)
2015

Correcting
Name

Employer identification number (EIN)

Calendar Year (YYYY)

Part 3: Continued
20.

Total. Amount from line 19 on page 2 . . . . . . . . . . . . . . . . . . . . . . .
.
If line 20 is less than zero:
• If you checked line 1, this is the amount you want applied as a credit to your Form CT-1 for the tax period in which you are
filing this form.
• If you checked line 2, this is the amount you want refunded or abated.
If line 20 is more than zero, this is the amount you owe. Pay this amount when you file this return. For information on how to
pay, see Amount you owe in the instructions for line 20.

Part 4: Explain your corrections for the calendar year you are correcting.
21.

Check here if any corrections you entered on a line include both underreported and overreported amounts.
Explain both your underreported and overreported amounts on line 23.

22.

Check here if any corrections involve reclassified workers. Explain on line 23.

23.

You must give us a detailed explanation for how you determined your corrections. See the instructions.

Part 5: Sign here. You must complete all three pages of this form and sign it.
Under penalties of perjury, I declare that I have filed an original Form CT-1 and that I have examined this adjusted return or claim and any schedules or
statements that are attached, and to the best of my knowledge and belief, they are true, correct, and complete. Declaration of preparer (other than taxpayer)
is based on all information of which preparer has any knowledge.



Print your
name here

Sign your
name here
Date

Print your
title here
add slashes

Best daytime phone

Paid Preparer Use Only

Check if you are self-employed .

Preparer’s name

PTIN

Preparer’s signature

Date

Firm’s name (or yours if
self-employed)

EIN

Address

Phone

City
Page 3

State

.

.

.

.

.

.

Add slashes

ZIP code
Form CT-1

X (Rev. 2-2014)
2015

Type of errors
you are
correcting

Form CT-1 X: Which process should you use?

Underreported
amounts
ONLY

Use the adjustment process to correct underreported amounts.
• Check the box on line 1.
• Pay the amount you owe from line 20 when you file Form CT-1 X.

Overreported
amounts
ONLY

The process you
use depends on
when you file
Form CT-1 X.

If you are filing Form CT-1 X
MORE THAN 90 days before
the period of limitations on
credit or refund for Form
CT-1 expires . . .

Choose either the adjustment process or the claim
process to correct the overreported amounts.
Choose the adjustment process if you want the
amount shown on line 20 credited to your Form
CT-1 for the period in which you file Form CT-1 X.
Check the box on line 1.
OR
Choose the claim process if you want the
amount shown on line 20 refunded to you or
abated. Check the box on line 2.

BOTH
underreported
and
overreported
amounts

The process you
use depends on
when you file
Form CT-1 X.

If you are filing Form CT-1 X
WITHIN 90 days of the
expiration of the period of
limitations on credit or refund
for Form CT-1 . . .

You must use the claim process to correct the
overreported amounts. Check the box on line 2.

If you are filing Form CT-1 X
MORE THAN 90 days before
the period of limitations on
credit or refund for Form CT-1
expires . . .

Choose either the adjustment process or both
the adjustment process and the claim process
when you correct both underreported and
overreported amounts.
Choose the adjustment process if combining
your underreported and overreported amounts
results in a balance due or creates a credit that
you want applied to Form CT-1.
• File one Form CT-1 X, and
• Check the box on line 1 and follow the
instructions on line 20.
OR
Choose both the adjustment process and the
claim process if you want the overreported
amount refunded to you or abated.
File two separate forms.
1. For the adjustment process, file one Form
CT-1 X to correct the underreported amounts.
Check the box on line 1. Pay the amount you
owe from line 20 when you file Form CT-1 X.

bold

If you are filing Form CT-1 X
WITHIN 90 days of the
expiration of the period of
limitations on credit or refund
for Form CT-1 . . .

2. For the claim process, file a second Form
CT-1 X to correct the overreported amounts.
Check the box on line 2.
You must use both the adjustment process and
the claim process.
File two separate forms:
1. For the adjustment process, file one Form
CT-1 X to correct the underreported amounts.
Check the box on line 1. Pay the amount you
owe from line 20 when you file Form CT-1 X.
2. For the claim process, file a second Form
CT-1 X to correct the overreported amounts.
Check the box on line 2.

Page 4

Form CT-1

X (Rev. 2-2014)
2015

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Instructions for Form CT-1 X
(Rev. February 2015)

Department of the Treasury
Internal Revenue Service

Adjusted Employer's Annual Railroad Retirement Tax Return or Claim for Refund
Section references are to the Internal Revenue Code
unless otherwise noted.

Future Developments

For the latest information about developments related to
Form CT-1 X and its instructions, such as legislation
enacted after they were published, go to www.irs.gov/
ct1x.

Reminders
Correcting Tier 1 Employee Additional Medicare Tax
withholding. Beginning in 2013, compensation
(including tips) and sick pay subject to Tier 1 Employee
Additional Medicare Tax withholding are reported on Form
CT-1, lines 6 and 12. Any errors discovered on a
previously filed Form CT-1 are corrected on Form CT-1 X,
lines 11 and 17. For more information about Tier 1
Employee Additional Medicare Tax withholding, see the
Instructions for Form CT-1 and go to IRS.gov and enter
“Additional Medicare Tax” in the search box. See the
instructions for lines 11 and 17 for more information on the
types of errors that can be corrected and how the
correction is reported on Form CT-1 X.
Tier 1 Employee tax rate for 2011 and 2012. In 2011
and 2012, the Tier 1 Employee tax rate was 4.2% and Tier
1 Employer tax rate was 6.2% (10.4% total). Be sure to
use the correct rate when reporting correct amounts on
lines 9 and 15.
Period of limitations to make certain corrections expired. Generally, you may correct overreported taxes on
a previously filed Form CT-1 if you file Form CT-1 X within
3 years of the date Form CT-1 was filed or 2 years from
the date you paid the tax reported on Form CT-1,
whichever is later. For purposes of the period of
limitations, Form CT-1 is considered filed on the last day
in February of the succeeding year if filed before that date.
The period of limitations to correct the qualified
employer's Tier 1 tax exemption for 2010 and the qualified
employer's Tier 1 tax credit for 2010 expired on February
28, 2014, for most employers. The lines formerly used for
these corrections were removed from Form CT-1 X. If the
period of limitations for any of these corrections is still
open, you will need to file the February 2013 revision of
Form CT-1 X. The February 2013 revision of Form CT-1 X
is available on IRS.gov.

General Instructions:
Understanding Form CT-1 X
What Is the Purpose of Form CT-1 X?
Use Form CT-1 X to correct errors on a previously filed
Form CT-1. Use Form CT-1 X to correct:

Oct 23, 2014

Tier 1 Employee tax, Tier 1 Employee Medicare tax,
Tier 1 Employee Additional Medicare Tax, and Tier 2
Employee tax; and
Tier 1 Employer tax, Tier 1 Employer Medicare tax, and
Tier 2 Employer tax.
Use Form 843, Claim for Refund and Request for
Abatement, to request a refund or abatement of assessed
interest or penalties. Do not request abatement of
assessed interest or penalties on Form CT-1 or Form
CT-1 X.
We use the terms “correct” and “corrections” on
Form CT-1 X and in these instructions to include
interest-free adjustments under sections 6205
and 6413 and claims for refund and abatement under
sections 6402, 6414, and 6404. See Rev. Rul. 2009-39 for
examples of how the interest-free adjustment and claim
for refund rules apply in 10 different situations. You can
find Rev. Rul. 2009-39, 2009-52 I.R.B. 951 at
www.irs.gov/irb/2009-52_IRB/ar14.html.

TIP

When you discover an error on a previously filed Form
CT-1, you must:
Correct that error using Form CT-1 X,
File a separate Form CT-1 X for each Form CT-1 that
you are correcting, and
File Form CT-1 X separately. Do not file Form CT-1 X
with Form CT-1.
If you did not file a Form CT-1 for one or more years,
do not use Form CT-1 X. Instead, file Form CT-1 for each
of those years. See also When Should You File Form
CT-1 X, later. However, if you did not file Forms CT-1
because you improperly treated workers as independent
contractors or nonemployees and are now reclassifying
them as employees, see the instructions for line 22, later.
Report the correction of underreported and
overreported amounts for the same tax period on a single
Form CT-1 X, unless you are requesting a refund or
abatement. If you are requesting a refund or abatement
and are correcting both underreported and overreported
amounts, file one Form CT-1 X correcting the
underreported amounts only and a second Form CT-1 X
correcting the overreported amounts.
You will use the adjustment process if you
underreported employment taxes and are making a
payment, or if you overreported employment taxes and
will be applying the credit to Form CT-1 for the period
during which you file Form CT-1 X. However, see the
Caution under Is There a Deadline for Filing Form CT-1 X,
later, if you are correcting overreported amounts during
the last 90 days of a period of limitations. You will use the
claim process if you overreported employment taxes and
are requesting a refund or abatement of the overreported
amount. Follow the chart on the back of Form CT-1 X for
help in choosing whether to use the adjustment process

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sufficient postage, and is postmarked by the U.S. Postal
Service on or before the due date, or sent by an
IRS-designated private delivery service on or before the
due date. If you do not follow these guidelines, we will
consider Form CT-1 X filed when it is actually received.
See Pub. 15 (Circular E) for more information on legal
holidays and IRS-designated private delivery services.

or the claim process. Be sure to provide a detailed
explanation on line 23 for each correction that you show
on Form CT-1 X.
Continue to report current year adjustments on Form
CT-1, line 14.
You have additional requirements to complete when
filing Form CT-1 X, such as certifying that you filed (or will
file) all applicable Forms W-2, Wage and Tax Statements,
and Forms W-2c, Corrected Wage and Tax Statements,
with the Social Security Administration (SSA). For
corrections of overreported Tier 1 and Tier 2 taxes, you
must make any certifications that apply to your situation.

Underreported tax. If you are correcting underreported
tax, you must file Form CT-1 X by the due date of the
return for the return period in which you discovered the
error and pay the amount you owe by the time you file.
Filing and paying on time generally will ensure that your
correction is interest free and not subject to failure-to-pay
or failure-to-deposit penalties. See What About Penalties
and Interest, later. For details on how to make a payment,
see the instructions for line 20, later.
If Form CT-1 X is filed late (after the due date of the
return for the return period in which you discovered the
error), you must attach an amended Form 945-A to Form
CT-1 X. Otherwise, the IRS may assess an “averaged”
failure-to-deposit penalty. The total tax reported on Form
945-A, line M, must match the corrected total tax (Form
CT-1, line 15 (line 13 for years ending before January 1,
2013), combined with any correction reported on Form
CT-1 X, line 20) for the year, less any previous
abatements and interest-free tax assessments.

Be sure to give us a detailed explanation on line 23 for
each correction you show on Form CT-1 X.
Do not use Form CT-1 X to correct Form 941,
941-SS, 943, 944, or 945. Instead, use the "X"
CAUTION
form that corresponds to those forms (Form
941-X, 943-X, 944-X, or 945-X).

!

Where Can You Get Help?
For help filing Form CT-1 X or for questions about RRTA
taxes and tax corrections, you can:
Call the IRS Business and Specialty Tax Line toll free at
1-800-829-4933 or 1-800-829-4059 (TDD/TTY for
persons who are deaf, hard of hearing, or have a speech
disability) Monday–Friday from 7:00 a.m. – 7:00 p.m. local
time (Alaska and Hawaii follow Pacific time);
Visit the IRS website at www.irs.gov/businesses and
click on the Employment Taxes link under Businesses
Topics; or
See Pub. 15 (Circular E), Employer's Tax Guide.

Example—You owe tax. On March 11, 2014, you
discovered that you underreported $1,000 of RRTA
compensation on your 2013 Form CT-1. File Form CT-1 X
and pay the amount you owe by March 2, 2015, because
you discovered the error in 2014, and March 2, 2015, is
the due date for that year. If you file Form CT-1 X before
March 2, 2015, pay the amount you owe by the time you
file.

See also How Can You Order Forms, Instructions, and
Publications from the IRS, later.

Overreported tax—adjustment process. If you
overreported tax and choose to apply the credit to Form
CT-1, file an adjusted return on Form CT-1 X as soon as
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
Form CT-1 X, later.

When Should You File Form CT-1 X?
File Form CT-1 X when you discover an error on a
previously filed Form CT-1.
However, if your only errors on Form CT-1 relate to
RRTA tax liabilities reported in Part II of Form CT-1 or on
Form 945-A, Annual Record of Federal Tax Liability, do
not 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 monthly totals. The daily entries are not required.
For more information about correcting RRTA tax liabilities
reported on Form 945-A, see the Form 945-A instructions.

Form CT-1 X cannot be used to correct
overreported amounts of Tier 1 Employee
CAUTION
Additional Medicare Tax unless the amounts
were not withheld from employee compensation.

!

Example—You want your credit applied to Form
CT-1. You filed your 2014 Form CT-1 on February 25,
2015, and payments were timely made. On May 4, 2015,
you discover that you overreported tax on your 2014 Form
CT-1. You file Form CT-1 X on June 3, 2015. The IRS
treats your credit as a tax deposit made on January 1,
2015. When you file your 2015 Form CT-1, include the
amount from Form CT-1 X, line 20, on the “Total railroad
retirement tax deposits” line of your 2015 Form CT-1.

Due dates. The due date for filing Form CT-1 X depends
on when you discover an error and if you underreported or
overreported tax. If you underreported tax, see
Underreported tax, later. For overreported amounts, you
may choose to either make an interest-free adjustment or
file a claim for refund or abatement. If you are correcting
overreported amounts, see Overreported tax—adjustment
process or Overreported tax—claim process, later.
If any due date falls on a Saturday, Sunday, or legal
holiday, you may file Form CT-1 X on the next business
day. If we receive Form CT-1 X after the due date, we will
treat Form CT-1 X as filed on time if the envelope
containing Form CT-1 X is properly addressed, contains

Overreported tax—claim process. If you overreported
tax on Form CT-1, you may choose to file a claim for
refund or abatement on Form CT-1 X any time before the
period of limitations on credit or refund expires on Form
CT-1. If you also need to correct any underreported
amounts, you must file another Form CT-1 X reporting
-2-

Instructions for Form CT-1 X (Rev. 2-2015)

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on the top of any attachments. If your address has
changed since you filed your Form CT-1, enter the
corrected information and the IRS will update your
address of record.

only corrections to the underreported amounts. See Is
There a Deadline for Filing Form CT-1 X, later.

!

CAUTION

You may not file a refund claim to correct Tier 1
Employee Additional Medicare Tax actually
withheld from employees.

Return You Are Correcting

Enter the calendar year of the Form CT-1 you are
correcting at the top of page 1. Enter the calendar year on
pages 2 and 3 and on any attachments. Be sure to write
your name, EIN, “Form CT-1 X,” and the calendar year
you are correcting on the top of any attachments.

Is There a Deadline for Filing Form
CT-1 X?
Generally, you may correct overreported taxes on a
previously filed Form CT-1 if you file Form CT-1 X within 3
years of the date Form CT-1 was filed or 2 years from the
date you paid the tax reported on Form CT-1, whichever is
later. You may correct underreported taxes on a
previously filed Form CT-1 if you file Form CT-1 X within 3
years of the date the Form CT-1 was filed. We call each of
these time frames a “period of limitations.” For purposes
of the period of limitations, Form CT-1 is considered filed
on the last day in February of the succeeding year if filed
before that date.

Enter the Date You Discovered Errors

You must enter the date you discovered errors. You
discover an error when you have enough information to be
able to correct it. If you are reporting several errors that
you discovered at different times, enter the earliest date
you discovered an error here. Report any subsequent
dates and related errors on line 23.

Must You Make an Entry on Each Line?

You must provide all of the information requested at the
top of page 1 of Form CT-1 X. You must check one box
(but not both) in Part 1. In Part 2, you must check the box
on line 3 and any applicable boxes on lines 4 and 5. In
Part 3, if any line does not apply, leave it blank. Complete
Parts 4 and 5 as instructed.

Example. You filed your 2013 Form CT-1 on January
28, 2014, and payments were timely made. The IRS treats
the return as if it were filed on February 28, 2014. On
January 13, 2017, you discover that you overreported
RRTA compensation on that form by $10,000. To correct
the error you must file Form CT-1 X by February 28, 2017,
which is the end of the period of limitations, and use the
claim process.

How Should You Report Negative Amounts?

Form CT-1 X uses negative numbers to show reductions
in tax (credits) and positive numbers to show additional
tax (amounts you owe).

If you file Form CT-1 X to correct overreported
amounts in the last 90 days of a period of
CAUTION
limitations (after November 30, 2016, in the
example above), you must use the claim process. You
cannot use the adjustment process. If you also are
correcting underreported amounts, you must file another
Form CT-1 X to correct the underreported amounts using
the adjustment process and pay any tax due.

!

When reporting a negative amount in columns 3 and 4,
use a minus sign instead of parentheses. For example,
enter “-10.59” instead of “(10.59).” However, if you are
completing the return on your computer and your software
only allows you to use parentheses to report negative
amounts, you may use them.

Where Should You File Form CT-1 X?

How Should You Make Entries on Form CT-1 X?

Send your completed Form CT-1 X to:

You can help the IRS process Form CT-1 X timely and
accurately if you follow these guidelines.
Type or print your entries.
Use Courier font (if possible) for all typed or
computer-generated entries.
Omit dollar signs. You may use commas and decimal
points, if desired. Enter dollar amounts to the left of any
preprinted decimal point and cents to the right of it.
Always show an amount for cents. Do not round entries
to whole dollars.
Complete all three pages and sign Form CT-1 X on
page 3.
Staple multiple sheets in the upper-left corner.

Department of the Treasury
Internal Revenue Service Center
Cincinnati, OH 45999-0007

How Should You Complete Form CT-1
X?
Use a Separate Form CT-1 X for Each Year You
Are Correcting

Use a separate Form CT-1 X for each Form CT-1 that you
are correcting. For example, if you found errors on your
Forms CT-1 for 2013 and 2014, file one Form CT-1 X to
correct the 2013 Form CT-1. File a second Form CT-1 X
to correct the 2014 Form CT-1.

What About Penalties and Interest?

Generally, your correction of an underreported amount will
not be subject to a failure-to-pay penalty,
failure-to-deposit penalty, or interest if you:
File on time (by the due date of the year in which you
discover the error),
Pay the amount shown on line 20 by the time you file
Form CT-1 X,

EIN, RRB Number, Name, and Address

Enter your EIN, RRB number, name, and address in the
spaces provided. Also enter your name and EIN on the
top of pages 2 and 3. Be sure to write your name, EIN,
“Form CT-1 X,” and the calendar year you are correcting
Instructions for Form CT-1 X (Rev. 2-2015)

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allow the IRS enough time to process the credit, you file
Form CT-1 X on February 8, 2016, and take the credit on
your 2016 Form CT-1.

Enter the date you discovered the error, and
Explain in detail the grounds and facts relied on to
support the correction.
No correction will be eligible for interest-free treatment
if any of the following apply.
The underreported amounts relate to an issue that was
raised in an examination of a prior period.
You knowingly underreported your employment tax
liability.
You received a notice and demand for payment.
You received a Notice of Determination of Worker
Classification.

Specific Instructions
Part 1: Select ONLY One Process
Because Form CT-1 X may be used to file either an
adjusted railroad retirement tax return or a claim for refund
or abatement, you must check one box on either line 1 or
line 2. Do not check both boxes.

1. Adjusted Railroad Retirement Tax Return

If you receive a notice about a penalty after you file this
return, reply to the notice with an explanation and we will
determine if you meet reasonable-cause criteria. Do not
attach an explanation when you file your return.

Check the box on line 1 if you are correcting
underreported amounts or overreported amounts and you
would like to use the adjustment process to correct the
errors.

Overview of the Process

If you are correcting both underreported amounts and
overreported amounts on this form, you must check this
box. If you check this box, any negative amount shown on
line 20 will be applied as a credit (tax deposit) to your
Form CT-1 for the year in which you are filing this form.
See Example—You want your overreported tax applied as
a credit on Form CT-1, earlier.

The process to correct a previously filed Form CT-1 or file
a claim is outlined below.
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 20, later.

Form CT-1 X cannot be used to correct
overreported amounts of Tier 1 Employee
CAUTION
Additional Medicare Tax unless the amounts
were not withheld from employee compensation.

Example—You underreported RRTA taxes. On
June 23, 2014, you discovered an error that results in
additional tax on your 2013 Form CT-1. File Form CT-1 X
by March 2, 2015, and pay the amount you owe by the
time you file. See When Should You File Form CT-1 X,
earlier. Do not attach Form CT-1 X to your 2014 Form
CT-1.
If you overreported the tax. If you overreported the
tax on a previously filed Form CT-1, choose one of the
following options.
Use the adjustment process. Check the box on line 1 to
apply any credit (negative amount) from line 20 to Form
CT-1 for the year during which you file Form CT-1 X.
Use the claim process. Check the box on line 2 to file a
claim on Form CT-1 X requesting a refund or abatement
of the amount shown on line 20.

!

If you owe tax. Pay the amount shown on line 20 by the
time you file Form CT-1 X. Generally, you will not be
charged interest if you file on time, pay on time, enter the
date you discovered the error, and explain the correction
on line 23.
If you have a credit. You overreported RRTA taxes (you
have a negative amount on line 20) and want the IRS to
apply the credit to Form CT-1 for the period during which
you filed Form CT-1 X. The IRS will apply your credit on
the first day of the Form CT-1 year during which you filed
Form CT-1 X. However, the credit you show on Form
CT-1 X, line 20, may not be fully available on your Form
CT-1 if the IRS corrects it during processing or you owe
other taxes, penalties, or interest. The IRS will notify you if
your claimed credit changes or if the amount available as
a credit on Form CT-1 was reduced because of unpaid
taxes, penalties, or interest.

To ensure that the IRS has enough time to
process a credit for an overreporting
adjustment in the year during which you file
Form CT-1 X, you are encouraged to file Form CT-1 X
correcting the overreported amount in the first 11 months
of a year. For example, if you discover an overreported
amount in December, you may want to file Form CT-1 X in
the first 11 months of the next year. However, there must
be 90 days remaining on the period of limitations when
you file Form CT-1 X. See the Caution under Is There a
Deadline for Filing Form CT-1 X, earlier. This should
ensure that the IRS will have enough time to process the
Form CT-1 X so that the credit will be posted before you
file Form CT-1, thus avoiding an erroneous balance due
notice from the IRS. See the example next.

TIP

Do not check the box on line 1 if you are
correcting overreported amounts and the period
CAUTION
of limitations on credit or refund for Form CT-1
will expire within 90 days of the date you file Form CT-1 X.
Instead, check the box on line 2. See Is There a Deadline
for Filing Form CT-1 X, earlier.

!

2. Claim

Check the box on line 2 to use the claim process if you are
correcting overreported amounts only and you are
claiming a refund or abatement for the negative amount
(credit) shown on line 20. Do not check this box if you are
correcting any underreported amounts on this form.

Example—You want your overreported tax applied
as a credit on Form CT-1. On December 18, 2015, you
discover you overreported your tax on your 2014 Form
CT-1 and want to choose the adjustment process. To
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employees, check all applicable boxes. Provide a
summary on line 23 of the amount of the corrections for
both the employees who provided written statements and
for those who did not.

You must check the box on line 2 if you have a credit
and the period of limitations on credit or refund for Form
CT-1 will expire within 90 days of the date you file Form
CT-1 X. See Is There a Deadline for Filing Form CT-1 X,
earlier.

You may not use Form CT-1 X to correct
overreported amounts of Tier 1 Employee
CAUTION
Additional Medicare Tax unless the amounts
were not withheld from employee compensation.

The IRS usually processes claims shortly after they are
filed. The IRS will notify you if your claim is denied,
accepted as filed, or selected to be examined. See Pub.
556, Examination of Returns, Appeal Rights, and Claims
for Refund, for more information.

!

4a. Check the box on line 4a if your overreported amount
includes each affected employee's share of overcollected
Employee RRTA taxes. You are certifying that you repaid
or reimbursed the prior year Employee RRTA taxes and
you received written statements from the employees
stating that they did not and will not receive a refund or
credit for the prior year taxes.

Unless the IRS corrects Form CT-1 X during
processing or you owe other taxes, penalties, or interest,
the IRS will refund the amount shown on line 20, plus any
interest that applies.

!

CAUTION

You may not file a refund claim to correct Tier 1
Employee Additional Medicare Tax actually
withheld from employees.

Example. The following is an example of the written
statement that is required from employees.
Employee name
Employer name
I have received a repayment of $_________ as
overcollected RRTA taxes for 20___. I have not
claimed a refund of or credit for the overcollected
taxes from the IRS or, if I did, that claim has been
rejected; and I will not claim a refund or a credit of the
amount.
Employee signature
Date
Do not send these statements to the IRS. Keep them
for your records. Generally, all employment tax records
must be kept for at least 4 years.

Part 2: Complete the Certifications
You must complete all certifications that apply by
checking the appropriate boxes. If all of your corrections
relate to underreported amounts, complete line 3 only;
skip lines 4 and 5 and go to Part 3.
If your corrections relate to overreported amounts, you
have a duty to ensure that your employees' rights to
recover overpaid Employee RRTA taxes that you withheld
are protected. The certifications on lines 4 and 5 address
the requirement to:
Repay or reimburse your employees for the
overcollection of Employee RRTA taxes, or
Obtain consents from your employees to file a claim on
their behalf.
For purposes of these certifications, Employee RRTA
taxes consist of Tier 1 Employee tax, Tier 1 Employee
Medicare tax, and Tier 2 Employee tax. Employer RRTA
taxes consist of Tier 1 Employer tax, Tier 1 Employer
Medicare tax, and Tier 2 Employer tax.

4b. Check the box on line 4b to certify that your
overreported amount is only for Employer RRTA taxes on
those employees whom you were unable to find or those
who would not (or could not) give you a statement
described on line 4a.
4c. Check the box on line 4c to certify that your
overreported amount is only for RRTA taxes and/or Tier 1
Employee Additional Medicare Tax that you did not
withhold from your employees.

3. Filing Forms W-2 or Forms W-2c

Check the box on line 3 to certify that you filed or will file
Forms W-2 or Forms W-2c with the SSA, as required,
showing your employees' correct wage and tax amounts.
See the General Instructions for Forms W-2 and W-3 for
detailed information about filing requirements.

5. Certifying Claims

If you are filing a claim for refund or abatement of
overreported RRTA tax and/or Tier 1 Employee Additional
Medicare Tax and checked the box on line 2, check the
appropriate box on line 5. You may need to check more
than one box. If you obtained written statements or
consents from some employees but you could not locate
or secure the cooperation of the remaining employees,
check all applicable boxes. Provide a summary on line 23
of the amount of the corrections for the employees who
provided statements or consents and those who did not.

You must check the box on line 3 to certify that you filed
Forms W-2 or Forms W-2c even if your corrections on
Form CT-1 X do not change amounts shown on those
forms. For example, if your only correction to Form CT-1
involves misstated tax adjustments (see the instructions
for line 18), check the box on line 3 to certify that you
already filed all required Forms W-2 and W-2c with the
SSA.

!

4. Certifying Overreporting Adjustments

CAUTION

If you overreported RRTA tax and/or Tier 1 Employee
Additional Medicare Tax and checked the box on line 1,
check the appropriate box on line 4. You may need to
check more than one box. If you obtained written
statements from some employees but you could not
locate or secure the cooperation of the remaining

Instructions for Form CT-1 X (Rev. 2-2015)

You may not file a refund claim to correct Tier 1
Employee Additional Medicare Tax actually
withheld from employees.

5a. Check the box on line 5a if your overreported tax
includes overcollected Employee RRTA taxes for each
affected employee. You are certifying that you repaid or
reimbursed to the employees their share of the prior year
Employee RRTA taxes and you received written
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instructions for line 21), provide details for each error on
line 23.

statements from those employees stating that they did not
and will not receive a refund or credit for the prior year
taxes.

If you previously adjusted or amended Form CT-1
using Form CT-1 X, or because of an IRS
CAUTION
examination change, show amounts in column 2
that include those previously reported corrections.

5b. Check the box on line 5b if your overreported tax
includes overcollected prior year Employee RRTA taxes
for each affected employee and you have not yet repaid or
reimbursed the Employee RRTA taxes. You are certifying
that you received consent from each affected employee to
file a claim on the employee share of those taxes and you
received written statements from those employees stating
that they did not and will not receive a refund or credit for
the overcollected taxes.

!

6. Tier 1 Employer Tax—Compensation

If you are correcting the compensation (other than tips
and sick pay) for the Tier 1 Employer tax you reported on
Form CT-1, line 1, enter the total corrected amount for all
employees in column 1. In column 2, enter the amount
you originally reported. In column 3, enter the difference
between columns 1 and 2. If you (or the IRS) previously
corrected the amount reported on Form CT-1, line 1, enter
in column 2 the amount after any previous corrections.

Example. The following is an example of the consent
and written statement that is required from employees
when you are filing a claim for refund and have not yet
paid or reimbursed the employee share of taxes.
Employee name
Employer name
I give my consent to have my employer (named
above) file a claim on my behalf with the IRS
requesting $_________ in overcollected RRTA taxes
for 20___. I have not claimed a refund of or credit for
the overcollected taxes from the IRS or, if I did, that
claim has been rejected; and I will not claim a refund
or a credit of the amount.
Employee signature
Date
Do not send these statements to the IRS. Keep them
for your records. Generally, all employment tax records
must be kept for at least 4 years.

line 6 (column 1)
-line 6 (column 2)
line 6 (column 3)

If the amount in column 2 is larger than
the amount in column 1, use a minus
sign in column 3.

Multiply the amount in column 3 by .062 (6.2% tax rate)
and enter the result in column 4.
line 6 (column 3)
x
.062
line 6 (column 4)

In certain situations, you may not have repaid or
reimbursed your employees or obtained their consents
prior to filing a claim, such as in cases where the period of
limitations on credit or refund is about to expire. In those
situations, file Form CT-1 X, but do not check a box on
line 5. Tell us on line 23 that you have not repaid or
reimbursed employees or obtained consents. However,
you must certify that you have repaid or reimbursed your
employees or obtained consents before the IRS can grant
the claim.

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

Example—Tier 1 Employer compensation
decreased. You reported $9,000 as Tier 1 Employer
compensation in computing the tax on line 1 of your 2013
Form CT-1. In December of 2014, you discovered that you
included $2,000 in compensation for one of your
employees twice. To correct the error, figure the
difference on Form CT-1 X as shown.

5c. Check the box on line 5c to certify that your
overreported tax is only for the Employer RRTA taxes.
Affected employees did not give you consent to file a
claim for refund for the Employee RRTA taxes, they could
not be found, or they would not (or could not) give you a
statement described on line 5b.

Column 1 (corrected amount)
Column 2 (Form CT-1, line 1)

7,000.00
- 9,000.00

Column 3 (difference)

-2,000.00

Use the difference in column 3 to determine your tax
correction.

5d. Check the box on line 5d to certify that your
overreported amount is only for RRTA taxes and/or Tier 1
Employee Additional Medicare Tax that you did not
withhold from your employees.

Column 3 (difference)
Tax rate (6.2%)

Part 3: Enter the Corrections for the
Calendar Year You Are Correcting

Column 4 (tax correction)

-2,000.00
x .062
-124.00

Be sure to explain the reasons for this correction on
line 23.

What Amounts Should You Report in Part 3?

On lines 6–18, columns 1 and 2, show amounts for all of
your employees, not just for those employees whose
amounts you are correcting.

7. Tier 1 Employer Medicare
Tax—Compensation

If you are correcting the compensation (other than tips
and sick pay) for the Tier 1 Employer Medicare tax you

If a correction that you report in column 4 includes both
underreported and overreported amounts (see the
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in column 3 used a minus sign, also use a minus sign in
column 4.

reported on Form CT-1, line 2, 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.

Example—Tier 2 Employer compensation
decreased. Following Example—Tier 1 Employer
compensation decreased in the instructions for line 6, the
compensation that you counted twice was also Tier 2
Employer compensation. Because you are correcting your
2013 Form CT-1 in this example, use the rate from line 3
(12.6%) shown on that return. To correct the error, figure
the difference on Form CT-1 X as shown.

line 7 (column 1)
-line 7 (column 2)
line 7 (column 3)

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

Multiply the amount in column 3 by .0145 (1.45% tax
rate) and enter that result in column 4.
line 7 (column 3)
x .0145
line 7 (column 4)

Column 3 (difference)

-2,000.00

Column 4 (tax correction)

-2,000.00

-2,000.00
x .126

Column 4 (tax correction)

-252.00

Be sure to explain the reasons for this correction on
line 23.

9. Tier 1 Employee Tax—Compensation

If you are correcting the compensation, including tips
reported, but excluding sick pay, for the Tier 1 Employee
tax you reported on Form CT-1, line 4, 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.

Use the difference in column 3 to determine your tax
correction.
Column 3 (difference)
Tax rate (1.45%)

Column 3 (difference)

Column 3 (difference)
Tax rate (12.6%)

Example—Tier 1 Employer Medicare
compensation decreased. Following Example—Tier 1
Employer compensation decreased in the instructions for
line 6, the compensation that you counted twice was also
Tier 1 Employer Medicare compensation. To correct the
error, figure the difference on Form CT-1 X as shown.
7,000.00
- 9,000.00

7,000.00
- 9,000.00

Use the difference in column 3 to determine your tax
correction.

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

Column 1 (corrected amount)
Column 2 (Form CT-1, line 2)

Column 1 (corrected amount)
Column 2 (Form CT-1, line 3)

-2,000.00
x .0145

line 9 (column 1)
-line 9 (column 2)

-29.00

line 9 (column 3)

Be sure to explain the reasons for this correction on
line 23.

If the amount in column 2 is larger than
the amount in column 1, use a minus
sign in column 3.

Multiply the amount in column 3 by .062 (.042 for
corrections to a 2011 or 2012 return) and report that result
in column 4.

8. Tier 2 Employer Tax—Compensation

If you are correcting the compensation (other than tips) for
the Tier 2 Employer tax you reported on Form CT-1, line 3,
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.

line 9 (column 3)
x .062**
line 9 (column 4)

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

**Use .042 for corrections to a 2011 or 2012 return.

line 8 (column 1)
-line 8 (column 2)
line 8 (column 3)

Be sure to explain the reasons for this correction on
line 23.

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

10. Tier 1 Employee Medicare
Tax—Compensation

If you are 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

Multiply the amount in column 3 by the rate stated on
line 3 of the Form CT-1 for the year that you are
correcting and enter that result in column 4. If the amount
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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.

line 11 (column 3)
x .009
line 11 (column 4)

line 10 (column 1)
-line 10 (column 2)
line 10 (column 3)

Example—Prior year administrative error
(incorrectly reported amount of Tier 1 Employee
Additional Medicare Tax actually withheld).
Employee A's compensation exceeded the $200,000
withholding threshold for Tier 1 Employee Additional
Medicare Tax in November 2014. The total compensation
paid to Employee A for 2014 was $230,000. You withheld
$270 ($30,000 x .009) from the employee's
compensation. However, on your 2014 Form CT-1 you
mistakenly reported $3,000 on line 6 (Compensation
column), and Tier 1 Employee Additional Medicare Tax
withheld of $27 on line 6 (Tax column). You discover the
error on March 16, 2015. This is an example of an
administrative error that may be corrected in a later
calendar year because the amount actually withheld
differs from the amount reported on your 2014 Form CT-1.
Use Form CT-1 X, line 11, to correct the error as shown
below.

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

Multiply the amount in column 3 by .0145 (1.45% tax
rate) and enter that result in column 4.
line 10 (column 3)
x .0145
line 10 (column 4)

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

Be sure to explain the reasons for this correction on
line 23.

11. Tier 1 Employee Additional Medicare
Tax—Compensation (Other Than Sick Pay)

Column 1 (corrected amount)
Column 2 (Form CT-1, line 6
(Compensation column))
Column 3 (difference)

Generally, you may correct errors to Tier 1 Employee
Additional Medicare Tax withholding only if you
discovered the errors in the same calendar year the
compensation was paid to employees. However, you may
correct errors to Tier 1 Employee Additional Medicare Tax
withholding for prior years if the amount reported on Form
CT-1, line 6, does not agree with the amount you actually
withheld. This type of error is an administrative error.

30,000.00
- 3,000.00
27,000.00

Use the difference in column 3 to determine your tax
correction.
Column 3 (difference)
Tax rate (0.9%)

If a prior year error was a nonadminstrative error, you
may correct only the compensation subject to Tier 1
Employee Additional Medicare Tax withholding that was
originally reported on Form CT-1, line 6, or previously
corrected on Form CT-1 X. You cannot correct the tax
reported on Form CT-1, line 6.

Column 4 (tax correction)

27,000.00
x .009
243.00

Be sure to explain the reasons for this correction on
line 23.

Prior year administrative error. If you are correcting
the compensation subject to Tier 1 Employee Additional
Medicare Tax withholding that you reported on Form
CT-1, line 6, 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.

Prior year nonadministrative errors. You may correct
only the compensation subject to Tier 1 Employee
Additional Medicare Tax withholding that you reported on
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.

line 11 (column 1)
-line 11 (column 2)
line 11 (column 3)

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

line 11 (column 1)
-line 11 (column 2)

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

line 11 (column 3)

Multiply the amount in column 3 by .009 (0.9% tax rate)
and enter that result in column 4.

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

Do not multiply the amount in column 3 by .009 (0.9%
tax rate). Leave column 4 blank and explain the reasons
for this correction on line 23.
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Example—Prior year nonadministrative error
(failure to withhold Tier 1 Employee Additional
Medicare Tax when required). Employee B's
compensation exceeded the $200,000 withholding
threshold for Tier 1 Employee Additional Medicare Tax in
December 2014. The total compensation paid to
Employee B for 2014 was $220,000. You were required to
withhold $180 ($20,000 x .009) but you withheld nothing
and did not report an amount on line 6 of your 2014 Form
CT-1. You discover the error on March 16, 2015. File
Form CT-1 X to correct the compensation subject to Tier 1
Employee Additional Medicare Tax withholding for your
2014 Form CT-1, but you may not correct the Tier 1
Employee Additional Medicare Tax withheld (column 4)
because the error involves a previous year and the
amount previously reported for the employee represents
the actual amount withheld from the employee during
2014.

Column 1 (corrected amount)
Column 2 (Form CT-1, line 6
(Compensation column))
Column 3 (difference)

-47,000.00

Determine the portion of compensation reported in
column 3 that is related to the administrative error
($47,000 - $20,000 (nonadministrative error) = $27,000
(administrative error)). Multiply this portion of column 3
by .009 (0.9% tax rate) to determine your tax correction.
Difference related to administrative error
Tax rate (0.9%)
Column 4 (tax correction)

27,000.00
x .009
243.00

Be sure to explain the reasons for these corrections on
line 23. You must also report that $20,000 of the amount
shown in column 3 was related to the correction of a prior
year nonadministrative error and $27,000 of the amount
shown in column 3 was related to the correction of an
administrative error.

Combination of prior year administrative and nonadministrative errors. If you are reporting both
administrative errors and nonadministrative errors for the
same prior year, 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. However, multiply
only the amount of compensation reported in column 3
that are related to administrative errors by .009 (0.9% tax
rate). Do not multiply any compensation reported in
column 3 that was related to nonadministrative errors
by .009 (0.9% tax rate). Use line 23 to explain in detail
your corrections. The explanation must include the
reasons for the corrections and a breakdown of the
amount reported in column 3 into the amounts related to
administrative errors and nonadministrative errors.

12. Tier 2 Employee Tax—Compensation

If you are correcting the compensation, including tips
reported, for the Tier 2 Employee tax you reported on
Form CT-1, line 7 (line 6 for years ending before January
1, 2013), 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.
line 12 (column 1)
-line 12 (column 2)

Example—Combination of prior year
administrative and nonadministrative errors.
Employee A's compensation exceeded the $200,000
withholding threshold for Tier 1 Employee Additional
Medicare Tax in November 2014. The total compensation
paid to Employee A for 2014 was $230,000. You withheld
$270 ($30,000 x .009) from the employee's
compensation. However, on your 2014 Form CT-1 you
mistakenly reported $3,000 on line 6 (Compensation
column), and Tier 1 Employee Additional Medicare Tax
withheld of $27 on line 6 (Tax column). The difference in
compensation subject to Tier 1 Employee Additional
Medicare Tax related to this administrative error is
$27,000 ($30,000 - $3,000).
Employee B's compensation exceeded the $200,000
withholding threshold for Tier 1 Employee Additional
Medicare Tax in December 2014. The total compensation
paid to Employee B for 2014 was $220,000. You were
required to withhold $180 ($20,000 x .009) but you
withheld nothing and did not report Employee B’s $20,000
in compensation subject to Tier 1 Employee Additional
Medicare Tax withholding on line 6 of your 2014 Form
CT-1.
You discover both errors on March 16, 2015. Use Form
CT-1 X, line 11, to correct the errors as shown below.

Instructions for Form CT-1 X (Rev. 2-2015)

50,000.00
- 3,000.00

line 12 (column 3)

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

Multiply the amount in column 3 by the rate stated on
line 7 (line 6 for years ending before January 1, 2013)
of the Form CT-1 for the year that you are correcting
and enter that result in column 4. If the amount in column
3 used a minus sign, also use a minus sign in column 4.
Example—Tier 2 Employee compensation
decreased. Following Example—Tier 1 Employer
compensation decreased in the instructions for line 6, the
compensation that you counted twice was also Tier 2
Employee compensation. Because you are correcting
your 2013 Form CT-1 in this example, use the rate for
line 7 (4.4%) shown on that return. To correct the error,
figure the difference on Form CT-1 X as shown.
Column 1 (corrected amount)
Column 2 (Form CT-1, line 7)

7,000.00
- 9,000.00

Column 3 (difference)

-2,000.00

Use the difference in column 3 to determine your tax
correction.
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Column 3 (difference)
Tax rate (4.4%)

-2,000.00
x .044

Column 4 (tax correction)

In column 3, enter the difference between columns 1 and
2.

-88.00

line 14 (column 1)
-line 14 (column 2)

Be sure to explain the reasons for this correction on
line 23.

line 14 (column 3)

13. Tier 1 Employer Tax—Sick Pay

If you are correcting the sick pay for the Tier 1 Employer
tax you reported on Form CT-1, line 8 (line 7 for years
ending before January 1, 2013), 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.

Multiply the amount in column 3 by .0145 (1.45% tax
rate) and enter that result in column 4.
line 14 (column 3)
x .0145
line 14 (column 4)

line 13 (column 1)
-line 13 (column 2)
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.

Multiply the amount in column 3 by .062 (6.2% tax rate)
and enter that result in column 4.
line 13 (column 3)
x .062
line 13 (column 4)

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

Example—Tier 1 Employer sick pay increased.
You reported $8,000 as Tier 1 Employer sick pay in
computing the tax on line 8 of your 2014 Form CT-1. In
December of 2015, you discover that you overlooked
$1,000 in sick pay for one of your employees. To correct
the error, figure the difference on Form CT-1 X as shown.
Column 1 (corrected amount)
Column 2 (Form CT-1, line 8)
Column 3 (difference)

9,000.00
- 8,000.00

15. Tier 1 Employee Tax—Sick Pay

If you are correcting the sick pay for the Tier 1 Employee
tax you reported on Form CT-1, line 10 (line 9 for years
ending before January 1, 2013), 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.
line 15 (column 1)
-line 15 (column 2)
line 15 (column 3)

Column 4 (tax correction)

62.00

Be sure to explain the reasons for this correction on
line 23.

14. Tier 1 Employer Medicare Tax—Sick Pay

If you are correcting the sick pay for the Tier 1 Employer
Medicare tax you reported on Form CT-1, line 9 (line 8 for
years ending before January 1, 2013), enter the total
corrected amount in column 1. In column 2, enter the
amount you originally reported or as previously corrected.

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

Multiply the amount in column 3 by .062 (.042 for
corrections to a 2011 or 2012 return) and enter that result
in column 4.
line 15 (column 3)
x .062**

1,000.00

1,000.00
x .062

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

Be sure to explain the reasons for this correction on
line 23.

line 15 (column 4)

Use the difference in column 3 to determine your tax
correction.
Column 3 (difference)
Tax rate (6.2%)

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

**Use .042 for corrections to a 2011 or 2012 return.

Be sure to explain the reasons for this correction on
line 23.

16. Tier 1 Employee Medicare Tax—Sick Pay

If you are correcting the sick pay for the Tier 1 Employee
Medicare tax you reported on Form CT-1, line 11 (line 10
for years ending before January 1, 2013), 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.

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line 16 (column 1)
-line 16 (column 2)
line 16 (column 3)

If the amount in column 2 is larger
than the amount in column 1, use a
minus sign in column 3.

Multiply the amount in column 3 by .0145 (1.45% tax
rate) and enter that result in column 4.
line 16 (column 3)
x .0145
line 16 (column 4)

You may need to report negative numbers in any
column. Make sure that the difference you enter
in column 3 accurately represents the change to
adjustments originally reported or previously corrected on
Form CT-1, line 14 (line 12 for years ending before
January 1, 2013).

TIP

If the amount in column 3 used a minus sign,
also use a minus sign in column 4.

Be sure to explain the reasons for this correction on
line 23.

17. Tier 1 Employee Additional Medicare
Tax—Sick Pay

Generally, you may correct errors to Tier 1 Employee
Additional Medicare Tax withholding only if you
discovered the errors in the same calendar year the sick
pay was paid to employees. However, you may correct
errors to Tier 1 Employee Additional Medicare Tax
withholding for prior years if the amount reported on Form
CT-1, line 12, does not agree with the amount you actually
withheld. This type of error is an administrative error.
If a prior year error was a nonadminstrative error, you
may correct only the sick pay subject to Tier 1 Employee
Additional Medicare Tax withholding that was originally
reported on Form CT-1, line 12, or previously corrected on
Form CT-1 X. You cannot correct the tax reported on
Form CT-1, line 12.
For more information on the types of errors that can be
corrected on line 17, see the detailed examples in the
instructions for line 11.

18. Tax Adjustments

Do not enter an amount on line 18 unless you need to
correct any current year adjustments reported on Form
CT-1, line 14 (line 12 for years ending before January 1,
2013). However, if you need to correct sick pay
adjustments for prior years reported on Form CT-1, line 14
(line 12 for years ending before January 1, 2013), include
the corrections in the calculations of Form CT-1 X, lines
13–17.
Enter the corrected amount for tax adjustments in
column 1. Enter the originally reported or previously
corrected current year amount from Form CT-1, line 14,
(line 12 for years ending before January 1, 2013), in
column 2. In column 3, enter the difference between
columns 1 and 2.
line 18 (column 1)
-line 18 (column 2)
line 18 (column 3)

Instructions for Form CT-1 X (Rev. 2-2015)

Copy the amount in column 3 to column 4. Include any
minus sign shown in column 3.
On line 23, describe what you misreported on Form
CT-1. Tell us which current year adjustments have
changed, that is, fractions of cents; uncollected Tier 1
Employee tax, Tier 1 Employee Medicare tax, or Tier 2
Employee tax on tips; or credits for overpayments of
penalty or interest paid on tax for earlier years.
Only use line 18 to correct adjustments for
fractions of cents; uncollected Tier 1 Employee
CAUTION
tax, Tier 1 Employee Medicare tax, Tier 1
Employee Additional Medicare Tax, and Tier 2 Employee
tax on tips; or credits for overpayments of penalty or
interest previously reported. File a separate Form CT-1 X
for each year being corrected.

!

19–20. Total

Combine the amounts on lines 6–18 of column 4. Enter
the result on line 19. Copy the amount from line 19 on
page 2 to line 20 on page 3.
Example. You entered “-500.00” in column 4 of line 6,
“-100.00” in column 4 of line 7, and “1,400.00” in column 4
of line 18. Combine these amounts and enter “800.00” in
column 4 of line 19 and on line 20.
Line 6
Line 7
Line 18
Lines 19 and 20

-500.00
-100.00
+1,400.00
800.00

Your credit. If the amount entered on line 20 is less than
zero, for example, “-115.00,” you have a credit because
you overreported your RRTA taxes.
If you checked the box on line 1, include this amount
on Form CT-1, line 16 (“Total railroad retirement tax
deposits”) for the year during which you filed Form CT-1
X. Do not make any changes to your Record of Railroad
Retirement Tax Liability in Part II of Form CT-1 or on Form
945-A. The amounts reported on the record should reflect
your actual tax liability for the period.
If you checked the box on line 2, you are 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.
Amount you owe. If the amount entered on line 20 is a
positive number, you must pay the amount you owe by the
time you file Form CT-1 X. You may not use any credit that
you show on another Form CT-1 X to pay the amount you
owe, even if you filed for the amount you owe and the
credit at the same time.
If you owe tax and are filing a timely Form CT-1 X, do
not file an amended Form 945-A unless you were
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assessed a failure-to-deposit (FTD) penalty caused by an
incorrect, incomplete, or missing Form 945-A. Do not
include the tax increase reported on Form CT-1 X on any
amended Form 945-A you file.
If you owe tax and are filing a late Form CT-1 X, that is,
after the due date for Form CT-1 for the period in which
you discovered the error, you must file an amended Form
945-A with the Form CT-1 X. Otherwise, the IRS may
assess an “averaged” FTD penalty. The total tax reported
on Form 945-A, line M, must match the corrected tax
(Form CT-1, line 15 (line 13 for years ending before
January 1, 2013), combined with any correction reported
on Form CT-1 X, line 20) for the year, less any previous
abatements and interest-free tax assessments.
Payment methods. You may pay the amount you owe
on line 20 electronically using the Electronic Federal Tax
Payment System (EFTPS) or by a check or money order.
The preferred method of payment is EFTPS. For more
information, visit www.eftps.gov, call EFTPS Customer
Service at 1-800-555-4477 or 1-800-733-4829 (TDD) toll
free, or see Pub. 966, Electronic Federal Tax Payment
System: A Guide To Getting Started.
If you pay by check or money order, make it payable to
“United States Treasury.” On your check or money order,
be sure to write your EIN, “Form CT-1 X,” and the year
corrected.
You do not have to pay if the amount you owe is less
than $1.
Previously assessed FTD penalty. If line 20 reflects
overreported tax and the IRS previously assessed an FTD
penalty, you may be able to reduce the penalty. For more
information, see the Form 945-A instructions.

Part 4: Explain Your Corrections for
This Year
21. Correction of Both Underreported and
Overreported Amounts

Check the box on line 21 if any corrections you entered on
lines 6–18 in column 3 reflect both underreported and
overreported amounts.
Example. If you had an increase to Tier 1 Employer
compensation of $15,000 for employee A and a decrease
to Tier 1 Employer compensation of $5,000 for employee
B, you would enter $10,000 on line 6, column 3. That
$10,000 represents the net change resulting from
corrections.
On line 23, you must explain the reason for both the
$15,000 increase and the $5,000 decrease.

22. Did You Reclassify Any Workers?

Check the box on line 22 if you reclassified any workers to
be independent contractors or nonemployees. Also check
this box if the IRS (or you) determined that workers you
treated as independent contractors or nonemployees
should be classified as employees. On line 23, provide a
detailed reason why any worker was reclassified.
Return not filed because you did not treat any workers as employees. If you did not previously file Form
CT-1 because you mistakenly treated all workers as

independent contractors or as nonemployees, file a Form
CT-1 for each delinquent year.
Write “Misclassified Employees” in bold letters
across the top margin of page 1 of each Form CT-1.
Complete Form CT-1 using the Instructions for Form
CT-1. Attach a Form CT-1 X to each Form CT-1.
Complete the top of Form CT-1 X, including the date you
discovered the error, and provide a detailed explanation
on line 23.

23. Explain Your Corrections

Treasury regulations require you to explain in detail the
grounds and facts relied upon to support each correction.
On line 23, describe in detail each correction you entered
in column 4 on lines 6–18. If you need more space, attach
additional sheets, but be sure to write your name, EIN,
“Form CT-1 X,” and calendar year you are correcting on
the top of each sheet.
You must describe the events that caused the
underreported or overreported amounts. Explanations
such as “RRTA compensation was overstated” or
“administrative/payroll errors were discovered” are
insufficient and may delay the processing of your Form
CT-1 X because the IRS may need to ask for a more
complete explanation.
Provide the following information in your explanation of
each correction.
Form CT-1 X line number(s) affected.
Date you discovered the error.
Difference (amount of the error).
Cause of the error.
You may report the information in paragraph form. The
following paragraph is an example.
“The $1,000 difference shown in column 3 of lines 6
and 7 was discovered on May 14, 2014, during an internal
payroll audit. We discovered that we included $1,000 of
compensation for one of our employees twice. This
correction removes the reported compensation that was
never paid.”

Part 5: Sign Here
You must complete all three pages of Form CT-1 X and
sign it on page 3. If you do not sign, the processing of
Form CT-1 X will be delayed.
Who must sign the Form CT-1 X? The following
persons are authorized to sign the return for each type of
business entity.
Sole proprietorship—The individual who owns the
business.
Corporation (including a limited liability company
(LLC) treated as a corporation)—The president, vice
president, or other principal officer duly authorized to sign.
Partnership (including an LLC treated as a
partnership) or unincorporated organization—A
responsible and duly authorized partner, member, or
officer having knowledge of its affairs.
Single member LLC treated as a disregarded entity
for federal income tax purposes—The owner of the
LLC or a principal officer duly authorized to sign.
Trust or estate—The fiduciary.
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A duly authorized agent of the taxpayer also may sign
Form CT-1 X if a valid power of attorney has been filed.
Alternative signature method. Corporate officers or
duly authorized agents may sign Form CT-1 X by rubber
stamp, mechanical device, or computer software
program. For details and required documentation, see
Rev. Proc. 2005-39, 2005-28 I.R.B. 82, available at
www.irs.gov/pub/irs-irbs/irb05-28.pdf.

Paid Preparer Use Only

A paid preparer must sign Form CT-1 X and provide the
information in the Paid Preparer Use Only section of Part
5 if the preparer was paid to prepare Form CT-1 X and is
not an employee of the filing entity. Paid preparers must
sign paper returns with a manual signature. The preparer
must give the employer the return to file with the IRS and
include a copy of the return for the employer's records.
If you are a paid preparer, write your Preparer Tax
Identification Number (PTIN) in the space provided.
Include your complete address. If you work for a firm, write
the firm's name and the EIN of the firm. You can apply for
a PTIN online or by filing Form W-12, IRS Paid Preparer
Tax Identification Number (PTIN) Application and
Renewal. For more information about applying for a PTIN
online, visit the IRS website at www.irs.gov/ptin. You
cannot use your PTIN in place of the EIN of the tax
preparation firm.
Generally, you are not required to complete this section
if you are filing the return as a reporting agent and have a
valid Form 8655, Reporting Agent Authorization, 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 Order Forms,
Instructions, and Publications from
the IRS?
Visit the IRS website at www.irs.gov/formspubs.

Call the IRS at 1-800-TAX-FORM
(1-800-829-3676).

Additional Information

Form W-2, Wage and Tax Statement
Form W-3, Transmittal of Wage and Tax Statements
General Instructions for Forms W-2 and W-3
Form W-2c, Corrected Wage and Tax Statement
Form W-3c, Transmittal of Corrected Wage and Tax
Statements
Form 945-A, Annual Record of Federal Tax Liability
Form W-12, IRS Paid Preparer Tax Identification
Number (PTIN) Application and Renewal
Instructions for Form CT-1
Instructions for Form 843
Pub. 15 (Circular E), Employer's Tax Guide
Pub. 966, Electronic Federal Tax Payment System: A
Guide To Getting Started
Paperwork Reduction Act Notice. We ask for the
information on this form to carry out the Internal Revenue
laws of the United States. You are required to give us this
information. We need it to ensure that you are complying
with these laws and to allow us to figure and collect the
right amount of tax.
You are not required to provide the information
requested on a form that is subject to the Paperwork
Reduction Act unless the form displays a valid OMB
control number. Books or records relating to a form or its
instructions must be retained as long as their contents
may become material in the administration of any Internal
Revenue law. Generally, tax returns and return
information are confidential, as required by section 6103.
The time needed to complete and file Form CT-1 X will
vary depending on individual circumstances. The
estimated average time is:
Recordkeeping . . . . . . . . . . . . . . . . . . . . . . .
Learning about the law or the form . . . . . . . . .
Preparing and sending the form to the IRS . . . .

If you have comments concerning the accuracy of
these time estimates or suggestions for making this form
simpler, we would be happy to hear from you. You can
send us comments from www.irs.gov/formspubs. Click on
More Information and then click on Give us feedback. Or
you can write to the Internal Revenue Service, Tax Forms
and Publications Division, 1111 Constitution Ave. NW,
IR-6526, Washington, DC 20224. Do not send Form CT-1
X to this address. Instead, see Where Should You File
Form CT-1 X, earlier.

You may find the following forms, instructions, and
publications helpful when using Form CT-1 X.

Instructions for Form CT-1 X (Rev. 2-2015)

18 hr., 53 min.
24 min.
43 min.

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