Who needs one
- Non-residents filing Form 1040-NR
- Foreign owners claiming tax-treaty benefits that require a TIN
- Spouses and dependents on US returns
- Foreign partners receiving K-1s from US partnerships
How you get it
Form W-7, generally attached to a federal tax return, with your passport verified — either the original, an issuing-agency certified copy, or through a Certifying Acceptance Agent who checks it so you keep it. Expect 7–11 weeks.
Expiry
ITINs unused on a return for three consecutive years expire and need renewal before your next filing.
Go deeper
Related reading
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