ITIN (Individual Taxpayer Identification Number)

An ITIN is a nine-digit number issued by the IRS, formatted like an SSN but always beginning with 9. It exists only for federal tax reporting: it does not authorise work, confer immigration status, or qualify anyone for Social Security benefits or the Earned Income Credit. Expats meet it when a non-US spouse or dependent has to be identified on a return — for example to file jointly, or to claim a dependent. You apply on Form W-7, attached to the return the ITIN is needed for, with certified proof of identity and foreign status; a Certifying Acceptance Agent or a US consulate can certify documents so passports need not be mailed. An ITIN issued and then unused on a return for three consecutive years expires and must be renewed.