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Social Security Numbers

Excerpted from "Social Security Handbook". See the up-to-date, official Social Security Handbook at

1401. Social Security Numbers

1401.1 When is a Social Security Number assigned?

A Social Security Number (SSN) is assigned after we receive and process your completed application (Form SS-5, Application for a Social Security Card).

1401.2 What information do you submit with the application?

You must submit documents that prove your age, identity, and U.S. citizenship or immigration and work authorization status before we can process your application. If you are age 12 or older, you must apply in person for a social security card. Your identity document must show your legal name.

1401.3 How long does it take to process the application?

Usually, it takes about two weeks, but may take longer depending on how long it takes to verify your documents. For example, if you were born in the United States and are requesting an original Social Security number, we must verify your birth record, which can add up to 12 weeks to the time it takes to issue a card. U.S.-born includes birth in the 50 States, the District of Columbia, American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands.

1401.4 What is the SSN used for?

The SSN is used for the following purposes:

  1. SSA uses the SSN to record earnings covered by Social Security and/or Medicare. These earnings determine your eligibility and the amount of Social Security benefits when you retire, or become disabled; or survivor benefits if you die;

  2. The Internal Revenue Service (IRS) uses the numbers assigned to you and your dependents as your taxpayer identification numbers (TIN) for processing tax returns;

  3. You need a SSN to file for Social Security or Supplemental Security Income benefits, and Medicare; and

  4. If you have a SSN, State-run programs, such as State tax programs, driver's license, motor vehicle registration, and public assistance, may require that you provide your SSN.

1401.5 How does the SSN provide accurate identification?

Although the SSN card is not considered an identity document (because it does not display identifying information about you), SSA uses your SSN to differentiate you from other SSN card holders. Many people have the same name, but each person has his or her own SSN. Your SSN allows your earnings to be credited to you.

1401.6 Can a person use someone else's SSN?

No one else may lawfully use your SSN.

1401.7 Can a person have more than one SSN?

Most persons have only one SSN. In certain limited situations, SSA can assign you a new number. If you receive a new SSN, you should use the new number. However, your old and new number will remain linked in our records to ensure that your earnings are credited properly. This could affect your benefits.

Last Revised: Feb. 2, 2006



There are 6 Comments

Can someone please help me I was trying to buy a phone at t-mobile but they said someone have the same ssn number and have already bought phones with my social security number so know what do i do

can a social security new number can start with 0?

The Social Security number is divided as follows: the area number (first three digits), group number (fourth and fifth digits), and serial number (last four digits).

To determine if an SSN is invalid consider the following: No SSNs with an area number in the 800 or 900 series, or "000" area number, have been assigned.

See here for details to see if a Social Security number is valid :

We need to travel in 2 weeks due to a family emergency outside the US. My 5 year old daughter needs to renew her passport but we need her SSN to do so. We cannot find her card/number. If I go into social security office with appropriate documentation will they give me her number while card is being issued ?

I recommend contacting your local SSA office as you might be able to do this.

I have not seen an indication that the SSA will quickly provide a "number only" (no card). However, I have seen reports that folks are able to obtain a replacement card in one day.

If you have old tax returns, I'd check them as they likely will have your daughter's SSN there.


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