Social Security number

American  

[soh-shuhl si-kyoor-i-tee nuhm-ber] / ˈsoʊ ʃəl sɪˈkjʊər ɪ ti ˌnʌm bər /

noun

1. a unique nine-digit number assigned to each U.S. citizen and sometimes also given to resident non-citizens, used by the government for Social Security taxes, program eligibility, etc. SSN

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Etymology

Origin of Social Security number

First recorded in 1935–40

Example Sentences

See Examples For:

Social Security number

But any child who is under 18 and has a valid Social Security number can sign up for a Trump account.

From MarketWatch ● Jul. 23, 2026

When it comes to the $1,000 seed money, the IRS notes that it’s for babies who are U.S. citizens and have a valid Social Security number.

From MarketWatch ● Jul. 6, 2026

Kalshi requires users to give their address, at least part of their Social Security number, their phone number, date of birth and identity documentation.

From The Wall Street Journal ● Jun. 9, 2026

To register you’ll need to provide a driver’s license, a state identification number or the last four digits of your Social Security number.

From Los Angeles Times ● Jun. 2, 2026

We would attempt to say, “Correction-officer recruit,” and our name and Social Security number, during which time we would presumably learn how effective the gas was.

From "Newjack: Guarding Sing Sing" by Ted Conover