What is a Social Security Number (SSN)?

A Social Security Number (SSN) is a nine-digit number issued by the Social Security Administration (SSA) to U.S. citizens, permanent residents, and eligible temporary residents. It was created in 1936 primarily to track individuals for Social Security benefits, but is now widely used for tax reporting, credit applications, and identity verification.

What do the first three digits of an SSN mean?

The first three digits are called the Area Number. For SSNs issued before June 25, 2011, these digits indicated the geographic region where the SSN was applied for - typically the state of residence at the time of application. After June 25, 2011, SSNs are randomly assigned and the area number no longer indicates location.

What do the middle two digits of an SSN mean?

The middle two digits are called the Group Number. For pre-2011 SSNs, group numbers were assigned in a specific sequence: odd numbers 01-09 first, then even numbers 10-98, then even numbers 02-08, and finally odd numbers 11-99. This sequence helped estimate when an SSN was issued within an area's allocation period.

What do the last four digits of an SSN mean?

The last four digits are called the Serial Number. These are assigned sequentially from 0001 to 9999 within each group number. The serial number alone does not reveal any geographic or temporal information about the SSN holder.

Can you tell where someone was born from their SSN?

No. For SSNs issued before June 2011, the area number only indicates where the SSN was applied for, not where the person was born. Many people apply for SSNs in states different from their birthplace. For SSNs issued after June 25, 2011, the numbers are completely randomized and reveal nothing about location.

What is SSN randomization?

SSN randomization is a policy implemented by the SSA on June 25, 2011. Under this system, all three components of the SSN (area, group, and serial numbers) are assigned randomly rather than based on geographic location or sequential order. This change was made to extend the life of the SSN numbering system and enhance protection against identity theft.

Why is area number 666 never assigned?

Area number 666 was never assigned due to its negative connotations in Western culture, where it is often associated with the 'Number of the Beast' from the Book of Revelation. The SSA simply skipped this number when assigning area codes to avoid potential objections from SSN holders.

What is an ITIN and how is it different from an SSN?

An Individual Taxpayer Identification Number (ITIN) is a nine-digit number issued by the IRS to individuals who need to file taxes but are not eligible for an SSN. ITINs always begin with the number 9 and have a 7 or 8 in the fourth position (e.g., 9XX-7X-XXXX). Unlike SSNs, ITINs cannot be used for employment or Social Security benefits.

What SSN area numbers are considered invalid?

The following area numbers are always invalid: 000 (never assigned), 666 (skipped due to cultural reasons), and 900-999 (reserved for ITINs, not SSNs). Additionally, SSNs with group number 00 or serial number 0000 are invalid. Area numbers 800-899 were also never assigned for regular SSNs.

What is the Woolworth SSN (078-05-1120)?

078-05-1120 is the most misused SSN in history. In 1938, a wallet manufacturer put a sample Social Security card in each wallet sold at Woolworth stores. The card displayed the SSN of their secretary, Hilda Schrader Whitcher. Over 40,000 people reported using this number as their own, and the SSA voided it in 1943.

Can an SSN be reused after someone dies?

No. The Social Security Administration does not reassign SSNs after the holder dies. With approximately 453 million SSNs already assigned and about 5.5 million new numbers issued annually, the SSA estimates the current system has enough combinations to last several more generations before exhaustion.

What were Railroad Retirement SSNs (700-728)?

Area numbers 700-728 were assigned to railroad workers through the Railroad Retirement Board from 1936 until July 1, 1963. After that date, railroad workers received regular SSNs through the SSA. These numbers indicate the person worked for a railroad company before 1963, not their geographic location.

What is Enumeration at Entry (EAE)?

Enumeration at Entry is a program started in 2003 where immigrants can apply for an SSN as part of their immigration process. SSNs issued through EAE originally used area numbers 729-733. The program simplifies the SSN application process for newly arrived immigrants.

How can I verify if an SSN format is valid?

To verify basic SSN format validity: (1) It must be exactly 9 digits, (2) Area number cannot be 000, 666, or 900-999, (3) Group number cannot be 00, (4) Serial number cannot be 0000. However, format validity does not confirm the SSN was actually issued or belongs to a specific person - only the SSA can verify that.

What is the SSN High Group List?

The High Group List was a monthly publication by the SSA showing the highest group number assigned for each area number. It was used to verify if an SSN could have been legitimately issued. After randomization in 2011, the High Group List became obsolete for validating new SSNs, though it remains useful for pre-2011 numbers.

Why do some states have multiple SSN area number ranges?

States received additional area number ranges as their original allocations were exhausted. For example, California initially had 545-573, then received 602-626 in 1987 when the first range was depleted. Florida used 261-267, then 589-595, then 766-772 as demand increased over decades.

Can you estimate when an SSN was issued?

For SSNs issued before June 2011, you can estimate the issuance year using the area and group numbers. The area number indicates the state's assignment period, and the group number's position in the assignment sequence (odd 01-09, even 10-98, even 02-08, odd 11-99) shows approximately when within that period the SSN was issued.

What SSN area numbers were assigned to Puerto Rico?

Puerto Rico was assigned area numbers 581-584 (1936-1985) and later 596-599 (1985-2011). These numbers followed the same assignment rules as U.S. states. After randomization in 2011, Puerto Rico residents receive randomly assigned SSNs like everyone else.

What is the SSN Death Master File?

The Death Master File (DMF) is a database maintained by the SSA containing records of deceased individuals whose deaths were reported to the SSA. It includes the SSN, name, date of birth, and date of death. The file is used by government agencies and certain private entities to prevent fraud and identity theft.

How many SSNs have been issued in total?

As of 2023, approximately 453 million SSNs have been issued since the program began in 1936. With about 5.5 million new SSNs assigned each year and no reuse of numbers, the theoretical limit of around 1 billion valid combinations (excluding invalid patterns) should last well into the 22nd century.

What was the first SSN ever issued?

The lowest SSN ever issued was 001-01-0001, assigned to Grace D. Owen of Concord, New Hampshire in November 1936. The first SSNs were issued based on the geographic location of the Social Security field offices, starting with New England states which received the lowest area numbers.

Can a person have more than one SSN?

In rare circumstances, the SSA may issue a new SSN to someone who can prove they are being harassed, abused, or their life is endangered. Victims of identity theft may also receive new numbers in extreme cases. However, the SSA discourages this practice as it creates complications with credit history and government records.

What is SSN truncation?

SSN truncation refers to the practice of displaying only the last four digits of an SSN (often shown as XXX-XX-1234) to protect sensitive information. Many documents, receipts, and online accounts now use truncation as a security measure. The last four digits alone cannot uniquely identify an individual.

What are the Pacific Island SSN assignments?

Area number 586 was assigned to Pacific Island territories including Guam, American Samoa, the Philippines (until independence in 1946), and the Northern Mariana Islands. This single area number covered multiple island territories across the Pacific Ocean.

Why do some states have non-contiguous area number ranges?

States received additional area numbers as needed, but these were assigned from whatever ranges were available at the time, not necessarily adjacent to original allocations. For example, Mississippi has 425-428 (original), 587-588 (added 1964), and 752-755 (added 2007).

What happens if I lose my Social Security card?

You can request a replacement Social Security card from the SSA, either online, by mail, or in person at a local office. You are limited to three replacement cards per year and ten during your lifetime. Your SSN itself does not change when you get a replacement card.

When did babies start getting SSNs at birth?

The Enumeration at Birth (EAB) program began in 1987, allowing parents to request an SSN for their newborn through the birth registration process at the hospital. Before this, people typically applied for SSNs when they entered the workforce or needed one for tax purposes, often as teenagers or adults.

What is the LifeLock SSN (457-55-5462)?

457-55-5462 belonged to LifeLock CEO Todd Davis, who publicly displayed his SSN in advertisements to demonstrate confidence in his company's identity theft protection. His SSN was subsequently used fraudulently over a dozen times, and the number is now flagged as compromised in many verification systems.

Can non-citizens get Social Security Numbers?

Yes. Permanent residents (green card holders), temporary workers with valid work authorization, and certain other non-citizens can receive SSNs. The SSN card indicates work authorization status. Non-citizens without work authorization who need to file taxes may apply for an ITIN instead.

How does SSN verification work for employers?

Employers can verify SSNs through the Social Security Number Verification Service (SSNVS), which checks if the name and SSN match SSA records. E-Verify is another system that checks work authorization. These services confirm the SSN was issued and the name matches, but do not verify the person presenting it is the rightful owner.

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Phase 4 (Latest) Odd: 11, 13, 15 ... 97, 99

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Frequently Asked Questions About Social Security Numbers