How Many Social Security Numbers Do You Have?

So how many Social Security numbers do you have?

Social Security Card
Tom Grill | Photographer's Choice RF | Getty Images
Social Security Card

That may seem like a ridiculous question, but a recent study found more than 20 million Americans have multiple Social Security numbers associated with their name in commercial records.

The research was conducted by ID Analytics, a San Diego-based company that provides services to both detect identity fraud and to assess consumer identity risk and creditworthiness.

The study also found that rather than serving as a unique identifier, more than 40 million SSNs were associated with multiple people.

"Our research shows that Social Security numbers, contrary to popular perception, do not uniquely identify an individual," said Stephen Coggeshall, chief technology officer at ID Analytics.

Many of the duplicate numbers were the result of data entry errors as opposed to deliberate falsification, but the fact that these multiple numbers exist shows that it may be difficult for an organization to rely solely on the SSN to verify an individual's identity.

Telling consumers to be protective of their SSN, while sound advice, may inadvertently reinforce the idea that the SSN is an effective means of identification, according to Tom Oscherwitz, chief privacy officer at ID Analytics.

"Using the SSN as the sole means of identification and verification is a risky proposition," Oscherwitz said.

The study also found:

  • More than 100,000 Americans have five or more SSNs associated with their name.
  • More than 15 percent of SSNs are associated with two or more people.
  • More than 140,000 SSNs are associated with five or more people.
  • More than 27,000 SSNs are associated with 10 or more people.

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