Driver’s License Number Format by State: Numeric, Letter, Soundex

The driver’s license number format used by each state falls into one of three patterns: all digits, a mix of letters and digits, or an algorithmically generated string that encodes your name and date of birth. The Real ID Act of 2005 set security standards for the physical card but left the numbering scheme entirely to each state.1Department of Homeland Security. REAL ID That is why a Texas number is eight plain digits, a Florida number is a letter followed by twelve digits with your birthday buried inside, and a current Washington number begins with “WDL” and means nothing at all.

All-Numeric State Formats

A large group of states uses nothing but digits. Length depends on population and how long the state has been issuing licenses.

A few of these deserve a note. Colorado’s nine digits are usually printed as two, three, and four separated by hyphens. Mississippi’s nine digits are grouped exactly like a Social Security number, dashes in the same positions, which trips people up constantly; the two numbers are unrelated. New York’s nine-digit number is tied to you rather than the card, so it stays the same across renewals and replacements.4New York State Department of Motor Vehicles. Sample New York DMV Photo Documents Most other states work the same way, though a handful have reissued fresh numbers after switching systems.

Letter and Digit State Formats

Adding letters expands the pool of unique numbers without stretching the string much. Most letter-based formats use a single prefix, but some scatter letters through the number or place them at the end.

Single-Letter Prefix

  • One letter plus six digits: Delaware (variable length, one to seven digits)
  • One letter plus eight digits: Arizona, Kentucky, Nebraska, Virginia5U.S. Citizenship and Immigration Services. Arizona Drivers License and ID Card Information
  • One letter plus nine digits: Oklahoma

Arizona shows why old references can be wrong. The original Arizona license was all numeric, and older cards may still show that. Current Arizona licenses use one letter followed by eight digits.5U.S. Citizenship and Immigration Services. Arizona Drivers License and ID Card Information

Hawaii uses an “H” prefix followed by eight digits. Kansas uses a “K” prefix followed by eight digits. Louisiana numbers start with a zero. Massachusetts uses an “S” prefix (sometimes “SA”) followed by seven or eight digits. These single-letter prefixes function as state identifiers rather than encoded personal data.

Multi-Letter and Mixed Position Formats

  • Two letters plus six digits: Ohio
  • Three letters plus six digits: North Dakota
  • Two letters plus six digits plus a trailing letter: Idaho
  • Three digits, two letters, four digits: Iowa

Washington rebuilt its format in September 2018. Older Washington licenses encoded the driver’s name and birthdate into the number. The current format is “WDL” followed by nine randomly generated letters and digits, twelve characters total. The change was designed to remove personal data from a number that shows up on countless forms and databases.

States That Encode Your Name and Birthdate

Several states do not assign numbers randomly or in sequence. They run your name and date of birth through an encoding algorithm and build your license number from the output. Someone who knows the algorithm can pull an approximate last name, first name initial, and birthdate back out of the number.

The structure is consistent across these states: one letter (the first letter of your surname) followed by a long string of digits derived from Soundex plus birthdate encoding. The total length varies:

  • One letter plus twelve digits: Florida, Maryland, Michigan, Minnesota
  • One letter plus eleven digits: Illinois
  • One letter plus thirteen digits: Wisconsin
  • One letter plus fourteen digits: New Jersey

Maryland’s format is thirteen characters total: one letter followed by twelve digits.6U.S. Citizenship and Immigration Services. Maryland Drivers License and ID Card Information Separate segments within those digits encode the last name, first name, middle name, and date of birth. Maryland, Michigan, and Minnesota all use nearly identical schemes, sometimes called the shared format because the same algorithm produces numbers in each state.

Florida groups its letter and twelve digits with hyphens on the card. The first four characters are the Soundex code for the last name. The next three digits encode the first name and middle initial. Two digits give the birth year, three more encode the birth month and day (with different ranges for male and female drivers), and a final digit handles overflow when two people would otherwise receive the same number.

Illinois uses nearly the same breakdown: Soundex-coded surname, encoded first name, two-digit birth year, and a three-digit birth day code. The gender offset in Illinois adds 600 for female drivers. Wisconsin uses two overflow digits instead of one, which is why its number runs a character longer.

New Jersey takes a different route. Instead of Soundex, it uses an approximately linear numerical encoding of name characters, and it also encodes eye color into the final digit. The month-of-birth field doubles as a gender indicator, with 50 added to the month number for female drivers.

How Soundex Works

Soundex was developed for U.S. Census records to group similar-sounding surnames regardless of spelling. It converts a name into a letter followed by three digits. The letter is always the first letter of the surname. Remaining consonants get numeric values by sound:7National Archives. Soundex System

  • 1: B, F, P, V
  • 2: C, G, J, K, Q, S, X, Z
  • 3: D, T
  • 4: L
  • 5: M, N
  • 6: R

Vowels and the letters H, W, and Y are dropped. Adjacent consonants that share a code number collapse into a single digit. The result is always exactly four characters, padded with zeros if needed.7National Archives. Soundex System Under this system, Smith and Smyth both produce S-530, and Johnson and Jonson both produce J-525.

On a license number, that four-character Soundex code occupies the first four positions. The remaining digits encode other personal information using lookup tables that vary slightly by state. Two people with the same name and birthdate in the same state would generate identical base numbers, which is what the overflow digit at the end is there to resolve.

What Your Number Can Reveal About You

In states that use algorithmic encoding, your license number is a compressed copy of personal data. Someone who knows the scheme can pull out your approximate surname, first initial, date of birth, and in some states your gender or eye color. That matters because license numbers appear on far more paperwork than most people realize: insurance forms, court filings, rental car agreements, background check authorizations, and employment records.

Washington abandoned name-based encoding in 2018 and switched to random alphanumeric strings for exactly this reason. Other states using algorithmic formats have not followed. The encoding does not produce an exact name, only a Soundex approximation that fits many different surnames, but the birthdate portion is precise.

Federal law limits who can pull the personal information behind your number. Under 18 U.S.C. 2721, state motor vehicle agencies cannot disclose personal information from motor vehicle records except under specifically authorized circumstances, and a 1999 amendment requires express driver consent for most releases. Highly restricted personal information, which includes your photograph and Social Security number, gets stronger protection and cannot be disclosed without your explicit consent outside a narrow set of law enforcement and government purposes.8Office of the Law Revision Counsel. United States Code Title 18 – 2721 Prohibition on Release and Use of Certain Personal Information From State Motor Vehicle Records Individuals can sue for violations.

Entering Your Number Correctly on Forms

Format differences between states cause a large share of the data entry errors on insurance, court, and employment forms. A California number (one letter and seven digits) will fail validation on a system built for Texas (eight digits, no letters). A few practical points:

  • Include leading zeros. If your state issues numbers with leading zeros, they are part of the number. Dropping them creates a different, shorter number that will not match your record.
  • Ignore formatting characters. Hyphens, spaces, and dashes printed on the card are visual aids, not part of the number. Enter the raw string of letters and digits unless the form asks for the formatted version.
  • Match the card exactly. Some states have transitioned between formats, so an older license may show a different pattern than a current one. Enter what your card shows, not what a reference chart says your state should use.

If your card is lost, most states let you look the number up through the DMV portal using your name, date of birth, and Social Security number. Replacement cards run roughly $10 to $45 depending on the state. The number itself does not change when you replace the card.

Non-Driver ID Cards and Commercial Licenses

State-issued identification cards for residents who do not drive use the same format as driver licenses in that state. New York calls it your ID Number whether you hold a license or a non-driver ID, and the nine-digit format is identical.4New York State Department of Motor Vehicles. Sample New York DMV Photo Documents Pennsylvania assigns the same eight-digit format to both.2Commonwealth of Pennsylvania. Where to Find Your Drivers License Photo ID Number Both types qualify as List B identity documents on Form I-9.9U.S. Citizenship and Immigration Services. Handbook for Employers M-274 – 13.0 Acceptable Documents for Verifying Employment Authorization and Identity

Commercial driver licenses generally use the same number as the driver’s regular license. A CDL is not a separately numbered document; it replaces your standard license and carries the same state format. What sets a CDL apart is the class designation (A, B, or C) and any endorsement codes printed on the card, not the number itself.