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Protecting the Integrity of Social Security Numbers (SSNs)

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Social Security Administration (SSA).


Notice of enhancing the efficiency of SSA's SSN Assignment Process.


SSA is proposing to change the way that we assign SSNs. We intend to eliminate the geographical significance of the first three digits of the SSN (the “area number”) by no longer allocating entire area numbers for assignment to individuals in specific States. Instead, the SSN will be randomly assigned from the remaining pool of available SSNs, and the first three digits of the SSN will no longer have any geographical significance. We believe that by changing the way we assign the SSN we will ensure that there will be a reliable supply of SSNs for years to come. Additionally, we believe that this will also help reduce opportunities for identity theft and SSN fraud and misuse.

We specifically invite comments to help us determine whether this change would have any unanticipated effects on the public.


The agency must receive comments on or before August 2, 2007.


You may give us your comments: By Internet through the Federal eRulemaking Portal at; by e-mail to; by telfax to (410) 966-2830; or by letter to the Commissioner of Social Security, P.O. Box 17703, Baltimore, Maryland 21235-7703. You may also deliver them to the Office of Regulations, Social Security Administration, 107 Altmeyer Building, 6401 Security Boulevard, Baltimore, Maryland 21235-6401, between 8 a.m. and 4:30 p.m. on regular business days. Comments are posted on the Federal eRulemaking Portal. You may also inspect the comments on regular business days by making arrangements with the contact person shown in this preamble.

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Arthur L. LaVeck, Social Insurance Specialist, at (410) 966-5665.

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A. Background

SSA began assigning the nine-digit SSN in 1936 for the purpose of tracking workers' earnings over the course of their lifetime and to pay benefits. To date, we have assigned about 443 million of the almost one billion possible nine-digit combinations. For administrative reasons, certain number combinations will never be assigned.

Since its inception in 1936, the SSN has always been comprised of the three-digit area number, followed by the two-digit group number, and ending with the four-digit serial number. SSNs assigned before 1972 were issued by local SSA field offices and the area numbers reflected the State where the application for the number was made. Since 1972, SSA has issued Social Security cards centrally, and the area number reflects the State, as determined by the ZIP code in the mailing address of the application.

Over time, because of demographic shifts in the relative populations of the States, there have been more SSNs assigned in some States than originally projected, and fewer in other States.

B. Replacing Geographically Based Area Numbers by Randomly Assigning the SSN from Remaining Pool of Available SSNs

SSA currently has many years' worth of potential SSNs available for future assignment. However, because area numbers in the past were allocated for assignment in States based on then current demographic trends, the allocations of SSNs in some States will be exhausted more quickly than in others. As a result, given present rates of assignment and existing geographic allocations, there are fewer than 10 years' worth of SSNs currently available for assignment in several States.

We believe that by randomizing the assignment of SSNs and no longer allocating them by State, SSA will promote a more efficient distribution of SSNs, and it will ensure that all States have a sufficient supply of SSNs available for assignment for many years to come.

C. Randomizing the Area Number Will Help Protect Against Identity Theft

As the SSN has increasingly become an identifier used by both public and private entities, instances of SSN fraud/misuse and identity theft have also increased. We believe that another benefit of ending the geographic significance associated with the SSN area number is that opportunities for SSN fraud/misuse and identity theft will be reduced. By eliminating the geographical significance of the first three digits of the SSN, we can help prevent someone from learning an individual's SSN by acquiring the area number of a potential victim's SSN through knowledge of the date and/or location of the SSN application, and combining it with the correct group and serial number (i.e. the last four digits of the SSN), and being able to use that SSN for illegal purposes.

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Dated: June 27, 2007.

Michael J. Astrue,

Commissioner of Social Security.

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[FR Doc. E7-12831 Filed 7-2-07; 8:45 am]