Social Security Number

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In the U.S., an individual’s employment and earnings are tracked using their Social Security number (SSN). An SSN is a government-issued, unique, nine-digit number that every U.S. citizen and permanent resident can apply for, as well as eligible temporary residents.

In addition to tracking wages and employment, SSNs are also used to track taxes and Social Security contributions and benefits. You can also use your SSN and Social Security card as proof of identity. Your employer will use your SSN to report your earned income to the IRS. The earnings reported to your SSN determine your tax liabilities and your eligibility and compensation for things like disability, retirement benefits, and other social programs. 

You must have an SSN to work in the U.S legally. However, some temporary residents that are not permitted to work may also have a valid need for a Social Security card. So, the government also issues restricted cards for these individuals, which clearly state that they are not valid for employment purposes.

Since your SSN is directly tied to your identity, finances, and taxes, you will need your SSN to:

  • Apply for a passport or driver’s license
  • Open a new bank account 
  • Apply for government assistance or social programs
  • Apply for a loan or mortgage
  • Enroll in Medicare
  • File your tax return
  • Apply for Social Security benefits

Your SSN is located on your Social Security card. If your card is misplaced or damaged, you should also be able to find it on your W-2, pay stubs, and tax documents. However, you should replace your missing Social Security card as soon as possible. You can apply for a free replacement through the Social Security Administration.

See also: How to get a replacement social security card

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