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

Brokerage accounts require sensitive data, including a Social Security number, date of birth and home address.

From MarketWatch ● Jul. 14, 2026

The third time, their Social Security number will be flagged and they will be permanently banned from IPO access.

From MarketWatch ● Jun. 11, 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

Babies born from 2025 to 2028 who are American citizens and have a Social Security number are eligible for the seed money.

From Barron's ● May 28, 2026

Ever since Apa had to go four times to clear up some mistake with Joon’s Social Security number, he has become paranoid that people are trying to trick him.

From "A Step from Heaven" by An Na