Form 14039 is the IRS Identity Theft Affidavit. You file it when you know or suspect someone used your social security number or ITIN to file a fraudulent federal tax return, wrongly claimed you or your dependent, or used your number for a job. You can submit it online (the IRS's preferred method), by fax or by mail, but only once per incident.
Tax identity theft usually shows up as a rejected e-file, an IRS letter about a return you didn't file, or income on your account from an employer you've never worked for. Form 14039 tells the IRS to treat your account as a victim's, so it can place a marker for future protection. Everything here comes from the February 2026 revision of the form and the IRS identity theft guide for individuals.
When to file Form 14039, and when not to
Section B of the form lists the only three situations it's for. Check every one that applies:
- You know or suspect someone used your information to fraudulently file a federal tax return (there's a box if your spouse is also a victim).
- You or your dependent was fraudulently or incorrectly claimed as a dependent.
- Your SSN or ITIN was fraudulently used for employment.
If your situation isn't one of those, don't file it. The form says to report the incident to the Federal Trade Commission at IdentityTheft.gov instead and request an IP PIN. Two more 'don'ts' from the form itself:
- Don't use it if your dependent's identity was used by a parent or guardian to file taxes. The IRS says plainly that this isn't identity theft.
- Don't send a second one for the same incident. It only causes delays.
Signs your tax identity may have been stolen
The IRS lists these warning signs. None of them proves identity theft on its own, but each one is worth checking:
- Your tax return is rejected because a return was already filed with your number.
- A W-2 or 1099 arrives from an employer you didn't work for, or a 1099-G for unemployment benefits you never applied for.
- You're told about an EIN you didn't apply for, or you get an unreported income notice such as a CP2000.
- Your Social Security account shows wages you didn't earn, or you see password-reset alerts or account logins you didn't make.
- A data breach has exposed your details. The IRS says to consider filing Form 14039 in that case.
What the six sections ask for
| Section | What you provide | Required? |
|---|---|---|
| A | Who you're filing for (yourself, in reply to an IRS notice, a dependent, or another person) | Yes |
| B | How you're affected, plus a written explanation with dates | Yes |
| C | The victim's name, SSN or ITIN, current address and the address on the last return | Yes |
| D | The last return filed and the tax years you think were affected | Yes |
| E | Signature under penalty of perjury | Yes |
| F | Representative, conservator, parent or guardian details | Only if filing for someone else |
In section D, the tax year means the year on the return, not the year it was filed. The form's own example: enter 2024 for the 2024 return even though it was filed in 2025. If you don't know, write 'Unknown'.
Filing for someone else
Section F has five reasons to choose from, and each has its own paperwork. A surviving spouse of a deceased taxpayer needs no attachments, not even a death certificate. A court-appointed personal representative attaches the court certificate. Where no representative has been appointed, you attach a death certificate or formal notice of death. A conservator or someone authorised on Form 2848 attaches proof of that authority, and a parent or guardian of a dependent signs to confirm they can act for them.
How to send it
| Method | When to use it |
|---|---|
| Online at IRS.gov/dmaf/form/f14039 | The preferred method for most people (no attachments) |
| Fax 855-807-5720 | All others not replying to a notice; use a cover sheet marked 'Confidential' |
| Mail to Fresno, CA 93725 | All others, by post |
| The address or fax on your IRS notice | If you're replying to an IRS letter (box 2 in section A) |
| Stapled to the back of a paper return | If you can't e-file because your, your spouse's or your dependent's number was misused |
Pick one method only. And never send your original tax return to the identity theft address: file it where you'd normally file. The IRS estimates the form takes about 15 minutes to complete.
A freeze goes further than an alert by blocking new accounts until you lift it, and our guide to freezing your credit shows how to set one up at each bureau.
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What to do alongside the form
- Stop all contact with the thief: don't click links, open attachments or hand over information.
- Update your IRS Online Account password.
- Follow the instructions on any IRS letter or notice you've received.
- Follow the recovery steps at IdentityTheft.gov.
- Get an Identity Protection PIN. The IRS encourages everyone to opt in, online at IRS.gov/pin, by appointment at a Taxpayer Assistance Center, or with Form 15227 if you're eligible.
- Keep records of every letter, call and email, keep filing and paying tax as usual, and check whether your state tax agency needs anything.
If your dependent was claimed on someone else's return, the IRS guide notes that from 2024 returns it accepts an e-filed return even when a dependent has already been claimed, if the primary taxpayer includes a valid IP PIN. If you can't e-file, a paper return takes 6 to 8 weeks to process before the IRS looks at the claim. For wider protection beyond your tax account, see our comparison of identity theft protection services.
The verdict
If one of the three situations in section B fits, file Form 14039 online, once, and then get an IP PIN straight away, because that's what stops the same thing happening next year. If your problem is something else, such as a scam call, the form isn't for you: report it at IdentityTheft.gov.
Alongside the affidavit, a fraud alert on your credit file is quick to place, as our guide to placing a fraud alert explains.
Frequently asked questions
When should I file Form 14039?
When someone used your SSN or ITIN to file a fraudulent return, you or your dependent was wrongly claimed as a dependent, or your number was used for employment.
Can I file Form 14039 online?
Yes. Online is the IRS's preferred method, although attachments can't be added that way.
Should I file Form 14039 again if I haven't heard back?
No. The form says not to file another for the same incident because it causes delays.
What should I do after filing Form 14039?
Get an Identity Protection PIN, follow the steps at IdentityTheft.gov and keep filing and paying tax as usual.
