Taxpayer Identification Number

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When Is A Taxpayer Identification Number Needed?
https://www.ssa.gov/OP_Home/handbook/handbook.01/handbook-0101.html

You need a Taxpayer Identification Number (TIN) if you:

1. Have income that is reported to the Internal Revenue Service (IRS); or

2. You are claimed as a dependent on someone's Federal income tax return.

The IRS uses your SSN as your TIN if you have been assigned one. If you are not eligible for an SSN, you may apply for an Individual Taxpayer Identification Number (ITIN) from IRS. If you have any questions about use of TINs, contact the nearest IRS office.