Form CT-1 X - Mar 2023

Form CT-1X: How to correct errors on Form CT-1

Form CT-1X is used by railroad employers to correct errors on a previously filed Form CT-1, Employer’s Annual Railroad Retirement Tax Return. The form allows employers to report corrections to Railroad Retirement Tax Act (RRTA) taxes, including Tier 1 and Tier 2 taxes.

Who needs to file Form CT-1X

Form CT-1X is for railroad employers that have already filed Form CT-1 and later discover an error. It is a correction form for RRTA taxes, not an individual income tax form such as Form 1040-X.

Form CT-1X may be prepared by:

• Railroad employer payroll teams correcting misreported Tier 1 or Tier 2 compensation or taxes
• Tax professionals and CPAs preparing corrections on behalf of railroad employer clients
• Employers correcting worker classifications when compensation previously treated as nonemployee compensation is later determined to be subject to RRTA taxes

Adjustment process vs. claim process

Form CT-1X provides two correction processes. The appropriate process depends on whether the correction results in additional tax or a reduction in previously reported tax. Use the adjustment process when correcting underreported tax or when an overpayment will be applied as a credit to a future Form CT-1. Use the claim process when correcting overreported tax and requesting a refund or abatement. Only one process should be selected for each Form CT-1X.

What to gather before completing Form CT-1X

The following records can help ensure the correction is reported accurately:

• A copy of the original Form CT-1 being corrected
• Corrected compensation and tax amounts for the affected employees
• The date the error was discovered
• Any Forms W-2 or W-2c filed, or that will be filed, with the Social Security Administration
• A written explanation of the correction for line 43, including what changed and why

Deadlines for filing Form CT-1X

The deadline for Form CT-1X depends on the type of correction and the applicable statute of limitations. For correction purposes, Form CT-1 is generally treated as filed on the last day of February following the calendar year covered by the return if it was filed before that date.

The general time limits are:

• Underreported tax: generally within three years from the date Form CT-1 was filed
• Overreported tax: generally within three years from the date Form CT-1 was filed or two years from the date the tax was paid, whichever is later

Additional rules may apply depending on the circumstances of the correction, so the current Form CT-1X instructions should be reviewed before filing.

Common questions about Form CT-1X

Can one Form CT-1X correct several years?

No. A separate Form CT-1X is required for each Form CT-1 being corrected. For example, errors affecting Forms CT-1 for two different years require two separate Forms CT-1X.

Can Form CT-1X be completed online?

Form CT-1X can be completed using a fillable version, but the completed form must be printed and submitted to the IRS according to the current filing instructions. Form CT-1X is not filed electronically through the IRS.

Where is Form CT-1X sent?

Form CT-1X is submitted separately from the current Form CT-1, unless the Form CT-1X instructions provide an exception for a specific correction, such as certain worker classification adjustments.

Does Form CT-1X correct Forms 941, 943, 944 or 945?

No. Form CT-1X only corrects Form CT-1. The corresponding correction forms are Form 941-X for Form 941, Form 943-X for Form 943, Form 944-X for Form 944 and Form 945-X for Form 945.

What if the original Form CT-1 was never filed?

Form CT-1X cannot be used to file a missing Form CT-1. The original Form CT-1 should be filed for the applicable year instead.

Complete Form CT-1X with Lumin

Fill up the required information using Lumin’s fillable Form CT-1X template, including the corrected Tier 1 and Tier 2 amounts and the explanation for the correction. After completing the form, download a copy for printing, signing and mailing according to the IRS filing instructions.