Updated October 19, 2026. Quick answer: The Notice to Employee on Form W-2c says to compare the amounts on the corrected form with those on your income tax return. If the corrected amounts change your U.S. income tax, it says to file Form 1040-X with Copy B of the W-2c. A correction in box 5 also bears on Form 8959, and a return not yet filed takes Copy B of both the original W-2 and the W-2c.
What the Notice to Employee says
Copy C of Form W-2c, the copy for the employee’s records, carries a Notice to Employee. It opens with a plain description of the form: “This is a corrected Form W-2” “for the tax year shown in box c.” The notice then speaks to the most common worry, a return that is already in: “If you have filed an income tax return for the year shown, you may have to file an amended return.”
The form labels the other copies by purpose as well. Copy B is marked “To Be Filed With Employee’s FEDERAL Tax Return”, Copy C is marked “For EMPLOYEE’S RECORDS”, and Copy 2 is marked “To Be Filed With Employee’s State, City, or Local Income Tax Return”. Which box was corrected is described on Form W-2c boxes 1 to 20, and what the identification boxes mean is on Form W-2c boxes c to i.
Compare the amounts, then decide
The first instruction in the notice is a comparison: “Compare amounts on this form with those reported on your income tax return.” That is a task of reading, not of filing. Put the corrected form next to the return you filed for the year in box c and look at the lines the corrected boxes feed. Tax withheld is covered on Form 1040 line 25.
What follows from the comparison is also in the notice: “If the corrected amounts change your U.S. income tax, file Form 1040-X with Copy B of this Form W-2c to amend the return you already filed.”
Your situation at a glance
The notice covers four cases. The table sets out each one with the sentence the form uses.
| Your situation | What the Notice to Employee says |
|---|---|
| You already filed the return for the year in box c | “If you have filed an income tax return for the year shown, you may have to file an amended return.” |
| The corrected amounts change your U.S. income tax | “file Form 1040-X with Copy B of this Form W-2c to amend the return you already filed.” |
| There is a correction in box 5 | “use the corrected amount to determine if you need to file or amend Form 8959.” |
| You have not filed the return yet | “attach Copy B of the original Form W-2 you received from your employer and Copy B of this Form W-2c to your return when you file it.” |
The amended return itself is prepared on Form 1040-X. The part of that form where you describe what changed is covered on Parts II and III of Form 1040-X, and the lines for tax and credits are on Form 1040-X lines 6 to 11.
A correction in box 5 and Form 8959
Box 5 is Medicare wages and tips. The notice gives it a paragraph of its own: “If there is a correction in box 5, Medicare wages and tips, use the corrected amount to determine if you need to file or amend Form 8959.” “Attach an original or amended Form 8959 to Form 1040 or 1040-X, as applicable.”
For what Form 8959 is, see Form 8959 and Form 8959 Part 1, and for the tax it computes, see Additional Medicare Tax.
If you have not filed your return yet
A correction that arrives before filing is handled differently. The notice says: “If you have not filed your return for the year shown in box c, attach Copy B of the original Form W-2 you received from your employer and Copy B of this Form W-2c to your return when you file it.”
Nothing in that sentence asks for an amended return. It asks for both Copy B forms to be attached, the original one and the corrected one.
Where to ask questions, and the territories
The notice closes with a pointer: “For more information, contact your nearest Internal Revenue Service office.” It adds a note for employees in the territories: “Employees in American Samoa, the Commonwealth of the Northern Mariana Islands, Guam, or the U.S. Virgin Islands should contact their local taxing authority for more information.”
The notice also refers to a web page for developments: “For the latest information about Form W-2c and its instructions, such as legislation enacted after we release them”.
What your employer is told to do
The instructions given to employers set a timing expectation that you can hold up against what you received: “File Forms W-2c and W-3c as soon as possible after you discover an error.” “Also provide Form W-2c to employees as soon as possible.” If the form reached you late, that is the sentence to compare it to.
Edition and box numbers
The form read for this page is Form W-2c (Rev. 1-2026), the January 2026 edition, together with the 2026 General Instructions for Forms W-2 and W-3. Check the year and edition printed on the form you received, because box numbers can change between editions.
Common mistakes
- Filing an amended return for any corrected form. The notice ties it to a change: “If the corrected amounts change your U.S. income tax, file Form 1040-X with Copy B of this Form W-2c to amend the return you already filed.”
- Skipping Form 8959 after a box 5 correction. The notice says “If there is a correction in box 5, Medicare wages and tips, use the corrected amount to determine if you need to file or amend Form 8959.”
- Sending only the corrected form with an unfiled return. The notice says “attach Copy B of the original Form W-2 you received from your employer and Copy B of this Form W-2c to your return when you file it.”
Related: Form 1040-X, Parts II and III of Form 1040-X, Form 1040-X lines 6 to 11, Form 8959, and Form 8959 Part 1.
Sources
- Form W-2c, Corrected Wage and Tax Statement (Rev. January 2026), with Notice to Employee: https://www.irs.gov/pub/irs-pdf/fw2c.pdf
- General Instructions for Forms W-2 and W-3 (including Forms W-2c and W-3c): https://www.irs.gov/pub/irs-pdf/iw2w3.pdf
- IRS: About Form W-2c: https://www.irs.gov/forms-pubs/about-form-w-2-c
Read from the IRS documents linked above on October 19, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.