ITIN (Individual Taxpayer Identification Number).

In plain English

An Individual Taxpayer Identification Number (ITIN) is a nine-digit number the IRS gives to people who have a U.S. tax filing requirement but are not eligible for a Social Security number, such as certain nonresidents, foreign nationals, and their dependents. It always starts with the number 9 and is used only for federal tax purposes. You apply with Form W-7, usually alongside your tax return, and you may need to send original documents or use an authorized acceptance agent to verify your identity. An ITIN does not authorize work, provide Social Security benefits, or change your immigration status.

01Why it matters

If you earn income in the U.S. and have to file but cannot get a Social Security number, an ITIN is how you file legally and claim a refund or certain credits. ITINs can also expire if unused, which can delay a return if you do not renew in time.

02The math, step by step

Imagine you are a foreign national earning U.S. income and owe taxes, but you are not eligible for a Social Security number. You file Form W-7 with your tax return, send the required identity documents, and the IRS issues you an ITIN starting with 9 so your return can be processed.

03What this is NOT

04Receipts

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