How to find your ITIN number if you lost it

Where your ITIN is printed

Your ITIN is on the letter that assigned it, on the US tax returns you filed using it, and often on tax forms from US payers. Check these, roughly in order of how reliable they are:

USAGov’s advice for a lost ITIN starts with the second row: check copies of your previous tax returns for the ITIN you entered on the form.

One return won’t help: the one you sent with your first Form W-7. The IRS tells applicants to leave the SSN box blank on that return, and it writes the new ITIN onto its own copy before processing it. If you followed that instruction, your copy has an empty box. Look at a return from a later year instead. The same applies to a spouse or dependents who applied on your return: the returns you filed after their ITINs arrived will show their numbers.

Payers are allowed to mask your number on your copy. IRS rules let a withholding agent show only the last four digits of your ITIN on the recipient copies of Form 1042-S, and let most information-return filers do the same on your 1099. The IRS’s own copy has the full number, but yours may not.

Two people may also have it. If a tax preparer filed a return for you, ask them for a copy. If a Certifying Acceptance Agent handled your ITIN application, ask them too: the IRS says CAAs receive copies of their clients’ ITIN notices.

An ITIN is nine digits and always starts with 9; ITIN number format shows the layout. Don’t confuse it with an IRS Number (IRSN). The IRS issues an IRSN when someone files a return or makes a payment without a taxpayer identification number, and it appears on IRS letters about that return. It isn’t an ITIN, although Form W-7 asks for both.

Is there an online ITIN lookup?

No. The IRS has no online tool that finds an ITIN by name, and USAGov points only to your own records or a phone call to the IRS. Treat any website that offers an “ITIN lookup” with caution. The official record is held by the IRS, and it releases your details only after checking who you are.

How to get your ITIN from the IRS by phone

USAGov says to contact the IRS on 800-829-1040 to look up your ITIN. The IRS lists these numbers for individuals:

Deaf or hard of hearing callers can use TTY/TDD 800-829-4059.

The IRS doesn’t publish a script for lost-ITIN calls, but its general rule applies: representatives must verify your identity before discussing your personal information. Its checklist for callers includes birth dates, your filing status, a prior-year tax return and any letters the IRS has sent you. Since the number is the thing you’re missing, bring everything else.

1. 1

   Gather your details

   Your full legal name as you gave it on Form W-7, your date of birth, the mailing addresses you’ve used with the IRS, and any past return or IRS letter you still have.

2. 2

   Call the right number

   Use 800-829-1040 inside the US or 267-941-1000 from abroad.

3. 3

   Verify your identity

   Answer the representative’s questions. If you can’t be verified, the IRS won’t discuss your account.

4. 4

   Ask for the number and its status

   Ask whether the ITIN is active or has expired. If you want the letter again, ask about a reissued CP565; the IRS has a reissued version of the notice.

5. 5

   Store it properly

   Write the number down with your tax records and keep the letter somewhere secure.

If someone else is calling for you

A family member, preparer or agent can call only with your authorization. The IRS asks third parties to have your name and details, the tax return they’re calling about, and verbal or written authorization on Form 8821 (Tax Information Authorization) or Form 2848 (Power of Attorney). Tax professionals with a valid third-party authorization can use the IRS Practitioner Priority Service.

Don’t apply for a second ITIN

USAGov is direct about this: if your ITIN is lost, don’t apply for a new number. Several IRS rules explain why:

• Your ITIN stays yours. The IRS’s internal manual says that once an ITIN is assigned, it’s assigned solely to you and stays assigned, as active or inactive, unless it’s revoked. An expired ITIN isn’t a revoked one.
• Form W-7 asks. Line 6e asks whether you’ve ever received an ITIN or an IRSN, and line 6f asks for the number and the name it was issued under.
• A duplicate can be rejected. The manual lists a rejection reason for applicants who have been assigned multiple ITINs, telling them which number to use. A rejection comes as a CP567 notice, after weeks of waiting. ITIN rejected explains those letters.

A phone call takes less time than any application, so if you need the number for a return you’re about to file, call the IRS first.

Found it, but has it expired?

Once you have the number, check it’s still active. An ITIN expires if it isn’t used on a US federal tax return for any three consecutive tax years. Every ITIN assigned before 2013 that was never renewed has also expired.

You only need to renew if the ITIN will go on a federal tax return. You renew with a new Form W-7, checking “Renew an existing ITIN” and entering your old number on line 6f. If you still can’t find the number, the IRS lets you check the “No/Don’t know” box on line 6e, but the W-7 instructions say that including your previous ITIN and the name it was issued under avoids processing delays.

How to keep your ITIN where you can find it

Once you have the number again, a few habits stop this happening twice:

• Keep the CP565 safe. The notice tells you to keep it in a secure place with your other important documents. A scan stored somewhere secure is a useful backup.
• Keep your Form W-7 copy. The W-7 instructions tell you to keep a copy of your application. It also has the exact name your ITIN was issued under, which you need for a renewal.
• Use the same name every time. The IRS matches your ITIN to your name and date of birth. Filing under a different name can delay your return, and a return where the name and ITIN don’t match doesn’t count as using the ITIN.
• Tell the IRS when your name changes. Send a letter explaining the change, with documents such as a marriage certificate, to the ITIN Operation in Austin.