Part 1: Select ONLY One Process

Because Form 943-X may be used to file either an adjusted employment tax return or a claim for refund or abatement, you must check one box on either line 1 or line 2. Don’t check both boxes.

Correcting an employment tax credit. For lines 1 and 2, if you underreported an employment tax credit, treat it like you overreported a tax amount. If you overreported an employment tax credit, treat it like you underreported a tax amount. If you’re filing Form 943-X to adjust only an employment tax credit and you’re not correcting any overreported taxes on Form 943-X, lines 6–11, skip lines 4 and 5.

1. Adjusted Employment Tax Return Check the box on line 1 if you’re correcting underreported tax amounts or overreported tax amounts and you would like to use the adjustment process to correct the errors.

If you’re correcting both underreported tax amounts and overreported tax amounts on this form, you must check this box. If you check this box, any negative amount shown on line 25 will be applied as a credit (tax deposit) to your Form 943 for the year in which you’re filing this form. See Example—You want your overreported tax applied as a credit to Form 943 , earlier.

Caution: Form 943-X can’t be used to correct overreported amounts of Additional Medicare Tax unless the amounts weren’t withheld from employee wages.

If you owe tax. Pay the amount shown on line 25 by the time you file Form 943-X. Generally, you won’t be charged interest if you file on time, pay on time, enter the date you discovered the error, and explain the correction on line 41.

If you have a credit. You overreported employment taxes (you have a negative amount on line 25) and want the IRS to apply the credit on Form 943 for the period during which you filed Form 943-X. The IRS will apply your credit on the first day of the Form 943 year during which you filed Form 943-X. However, the credit you show on Form 943-X, line 25, may not be fully available on your Form 943 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 943 was reduced because of unpaid taxes, penalties, or interest.

Caution: Don’t check the box on line 1 if you’re correcting overreported tax amounts and the period of limitations on credit or refund for Form 943 will expire within 90 days of the date you file Form 943-X. See Is There a Deadline for Filing Form 943-X, earlier.

8 Instructions for Form 943-X (Rev. 2-2026)

2. Claim Check the box on line 2 to use the claim process if you’re correcting overreported tax amounts only and you’re claiming a refund or abatement for the negative amount (credit) shown on line 25. Don’t check this box if you’re correcting any underreported tax amounts on this form.

You must check the box on line 2 if you have a credit (a negative amount on line 25) and the period of limitations on credit or refund for Form 943 will expire within 90 days of the date you file Form 943-X. See Is There a Deadline for Filing Form 943-X , earlier.

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.

Unless the IRS corrects Form 943-X during processing or you owe other taxes, penalties, or interest, the IRS will refund the amount shown on line 25, plus any interest that applies.

Caution: You may not file a refund claim to correct federal income tax or Additional Medicare Tax actually withheld from employees.