Updated 5 min readBy the Elite B Taxes team
Quick answer
An ITIN is a tax ID for people who need to file or be listed on a U.S. tax return but can't get a Social Security number — often spouses and children of visa holders. You apply with Form W-7, usually attached to your federal tax return, along with original or certified identity documents such as a passport.
Key points
- An ITIN is only for tax purposes — it doesn't give work authorization.
- Most first-time applications must be sent with a federal tax return.
- A valid passport alone proves both identity and foreign status.
- ITINs not used on a federal return for three consecutive years expire.
Who needs an ITIN?
You may need an ITIN if you don't qualify for an SSN and you:
- Are a spouse or dependent listed on a U.S. tax return (for example, an H-4 spouse)
- Are a nonresident with U.S. income that requires a return
- Need to claim a tax treaty benefit
How do I apply for an ITIN?
The usual process is:
- Complete Form W-7 and choose the correct reason for applying
- Attach it to your completed federal tax return (unless an exception applies)
- Include original or certified copies of your identity documents
- Submit by mail to the IRS, through a Certifying Acceptance Agent, or at an IRS Taxpayer Assistance Center
Which documents do I need?
A current passport is the only stand-alone document that proves both identity and foreign status. Without one, you'll need a combination of other documents. Dependents may also need proof of U.S. residency, such as school or medical records.
Using a Certifying Acceptance Agent means you don't have to mail your original passport to the IRS for most applicants.
How long does it take to get an ITIN?
The IRS usually processes applications in several weeks, and longer during the filing season or if documents are missing. Applying with a complete package is the best way to avoid delays.
How do I renew an expired ITIN?
Renewals also use Form W-7 — tick the renewal box and include your existing ITIN. Renew before you file if the ITIN expired, or refunds and credits can be delayed.
This guide is general information, not tax or legal advice for your situation. Tax rules change — talk to a professional before acting.