SSN Prefix by State: Area Numbers, Unused Codes, and 2011 Change

For any Social Security Number issued before June 25, 2011, the first three digits point to the state or territory where the person applied for the card. That is what the SSN prefix by state tables show. The Social Security Administration assigned the lowest prefixes to the Northeast and worked westward, so 001 begins in New Hampshire and the highest pre-randomization blocks land in California and the Pacific. Numbers issued on or after June 25, 2011 are assigned randomly and carry no geographic meaning.1Social Security Administration. Social Security Number Randomization Frequently Asked Questions

What the First Three Digits Actually Tell You

The first three digits are called the area number. The SSA built the scheme in 1936 to organize paper applications at its Baltimore filing center, and each state received one or more blocks of area numbers sized to its population at the time. Fast-growing states later got supplemental blocks when their original ranges ran out.

The area number reflects where the person was living when they applied, not necessarily where they were born. Before 1972, it identified the SSA field office that processed the application. After 1972, the SSA assigned numbers centrally based on the mailing address on the application, but the geographic logic held until randomization.2Social Security Administration. Social Security Numbers One useful exception: for numbers issued after 1988 under the Enumeration at Birth program, the prefix reliably indicates the state of birth, because parents apply for the number when the child is born.

Prefix List for All 50 States, DC, and Territories

The ranges below cover every SSN issued before June 25, 2011.3Social Security Administration. Social Security Bulletin – Meaning of the Social Security Number

Northeast

  • New Hampshire: 001–003
  • Maine: 004–007
  • Vermont: 008–009
  • Massachusetts: 010–034
  • Rhode Island: 035–039
  • Connecticut: 040–049
  • New York: 050–134
  • New Jersey: 135–158
  • Pennsylvania: 159–211

Mid-Atlantic and Southeast

  • Maryland: 212–220
  • Delaware: 221–222
  • Virginia: 223–231
  • West Virginia: 232–236
  • North Carolina: 237–246
  • South Carolina: 247–251
  • Georgia: 252–260
  • Florida: 261–267, 589–595
  • District of Columbia: 577–579

Florida burned through its original seven area numbers by 1980 and received the second block (589–595) to keep up with population growth.

Midwest

  • Ohio: 268–302
  • Indiana: 303–317
  • Illinois: 318–361
  • Michigan: 362–386
  • Wisconsin: 387–399
  • Kentucky: 400–407
  • Tennessee: 408–415
  • Alabama: 416–424
  • Mississippi: 425–428, 587–588

South Central

  • Arkansas: 429–432
  • Louisiana: 433–439
  • Oklahoma: 440–448
  • Texas: 449–467, 627–645

Texas holds one of the widest allocations in the country. Its original 19 area numbers were supplemented with a second block of 19, for 38 total.

Plains and Mountain States

  • Minnesota: 468–477
  • Iowa: 478–485
  • Missouri: 486–500
  • North Dakota: 501–502
  • South Dakota: 503–504
  • Nebraska: 505–508
  • Kansas: 509–515
  • Montana: 516–517
  • Idaho: 518–519
  • Wyoming: 520
  • Colorado: 521–524
  • New Mexico: 525, 585
  • Arizona: 526–527, 600–601
  • Utah: 528–529
  • Nevada: 530

Wyoming and Nevada each got a single area number, reflecting how small their populations were when the SSA drew up the allocations.

West Coast and Pacific

  • Washington: 531–539
  • Oregon: 540–544
  • California: 545–573, 602–626
  • Alaska: 574
  • Hawaii: 575–576

California’s 54 area numbers across two blocks make it the largest allocation of any state.

Territories and Special Assignments

  • Puerto Rico: 580–584, 596–599
  • Virgin Islands: 580 (group numbers 01–18 only)
  • Guam: 586 (group numbers 01–18 only)
  • American Samoa: 586 (group numbers 20–28 only)
  • Railroad Retirement Board: 700–728

The Virgin Islands shared area number 580 with Puerto Rico and were distinguished only by group number ranges within that prefix. Guam and American Samoa similarly shared 586. Railroad workers covered under the Railroad Retirement Board received numbers from a separate 700-series block.3Social Security Administration. Social Security Bulletin – Meaning of the Social Security Number

Prefixes That Were Never Issued

Some three-digit combinations have always been invalid. The SSA has never assigned an area number of 000, and it permanently reserved 666 and the entire 900–999 range. If you see a number with any of those prefixes, it was not legitimately issued.1Social Security Administration. Social Security Number Randomization Frequently Asked Questions

What Changed on June 25, 2011

On that date, the SSA switched to randomized assignment for every new number. The area number no longer identifies a state, and every component of the nine digits is generated randomly within the excluded patterns above. The change was not retroactive, so anyone who received a number before that date still carries a geographic prefix that maps to the tables above.1Social Security Administration. Social Security Number Randomization Frequently Asked Questions

Two things pushed the SSA to make the switch. The old scheme was running out of numbers in high-growth states because each state had a fixed allocation, and the predictable geographic structure had become a security concern after researchers showed how much of an SSN could be guessed from a person’s date and state of birth.

Why the Old Prefix Still Matters

Even with randomization in place for new cards, the prefix on an older SSN still comes up in practical settings. Employers and financial institutions sometimes flag a number whose prefix does not fit an applicant’s stated history. Someone who says they grew up in California but presents a number starting in 001–003 may get additional verification questions. A mismatch is not proof of fraud, because families moved and parents sometimes applied for a child’s number from a different state, but it is a common reason for a second look.

Genealogists and public records researchers also use the prefix tables when working with the SSA’s Death Master File, which lists SSNs of deceased individuals. Cross-referencing a decedent’s prefix against the state tables gives a workable approximation of where the person entered the Social Security system, and for post-1988 numbers, of where they were born.