What an Illinois driver license number looks like
Your Illinois driver license number is a 12-digit code printed on the front of your card. It is not random — each digit or group of digits encodes information about you, and the format has been the same since the 1990s.
The number follows this pattern: the first digit is a code for your sex, the next eight digits are derived from your name and date of birth, and the last three digits are a sequence number assigned by the Secretary of State. You cannot choose or change this number; it is generated when your license is issued.
Understanding the format helps you verify that your card was issued correctly and recognize what information is embedded in it. It also helps you spot a fake or altered license, since the digits follow strict rules.
Key Takeaways
- Illinois driver license numbers are always 12 digits, with the first digit indicating sex (0 for female, 1 for male).
- Digits 2 through 9 are calculated from your last name, first name, and date of birth using a specific algorithm.
- The last three digits are a sequence number assigned by the Secretary of State's office when your license is issued.
- The format has remained unchanged since the 1990s, so all valid Illinois licenses follow the same structure.
Breaking down each part of the number
Position 1 (sex digit): This is either 0 or 1. The digit 0 indicates female, and 1 indicates male. This is the only part of the number that directly corresponds to a single piece of your personal information.
Positions 2–9 (name and date of birth): These eight digits are generated using an algorithm that takes your last name, first name, and date of birth as input. The Secretary of State's office does not publish the exact algorithm, but it is deterministic — the same name and birth date always produce the same eight digits. This is why two people with identical names and birth dates would have the same digits in positions 2–9 (though their sequence numbers would differ).
Positions 10–12 (sequence number): These three digits distinguish you from anyone else who shares your sex, name, and birth date. The Secretary of State assigns these numbers sequentially as licenses are issued. If you renew your license, your sequence number may change.
Why the format matters when you renew or replace your license
When you renew your Illinois driver license, you receive a new card with a new expiration date, but your license number stays the same. The Secretary of State's office does not reassign numbers during renewal.
If you replace your license because it was lost, stolen, or damaged, you also keep the same number. A replacement card is issued with the same 12-digit code as your original.
The only time your license number changes is if you legally change your name. Because positions 2–9 are derived from your name, a name change triggers a new number. You will need to explore for a new license through the Secretary of State's office and pay the replacement fee.
How to verify your license number is correct
You can check that your license number follows the correct format by confirming it is exactly 12 digits with no letters or special characters. The first digit should be 0 or 1. If your card shows anything different, contact the Secretary of State's office to report a potential error.
If you suspect your license number has been used fraudulently or you have concerns about identity theft, you can request a new number by explore for a replacement license. The Secretary of State will issue a new 12-digit code, and you will receive a new card in the mail.
License number vs. license plate number
Your driver license number is different from your vehicle registration number or license plate number. The license number is tied to you as a person and appears on your driver license card. A license plate number is tied to a specific vehicle and appears on the metal plate attached to your car.
When you register a vehicle in Illinois, the Secretary of State assigns a separate registration number. This number is unrelated to your driver license number and follows a different format.
What to do if your license number appears on someone else's card
If you discover that your license number has been duplicated on another person's card, contact the Illinois Secretary of State's office when ready. This is a serious issue that can affect your driving record and insurance history.
You will need to provide proof of your identity and explain the situation. The Secretary of State can investigate and issue you a new license number if fraud is confirmed. In the meantime, keep a copy of your original license and any correspondence with the Secretary of State's office in case disputes arise with law enforcement or your insurance company.
Frequently Asked Questions
Can I request a specific driver license number?
No. The Illinois Secretary of State generates your license number using the algorithm described above. You cannot request a vanity number or choose a specific sequence. The number is assigned automatically when your license is issued.
Does my license number change if I move to a different county in Illinois?
No. Your driver license number is statewide and does not change based on where you live within Illinois. If you move, you update your address with the Secretary of State, but your license number remains the same.
What if I was born on a leap day — does that affect my license number?
Your date of birth is recorded as it appears on your birth certificate. The algorithm that generates positions 2–9 of your license number uses this date. If you were born on February 29, that date is used in the calculation, and your license number will reflect it.
Is my license number the same as my driver license number on my insurance card?
Yes. Your insurance company uses your Illinois driver license number as your identifier on your insurance card and in their records. It is the same 12-digit number printed on your physical license card.
Can I look up someone's driver license number if I know their name and birth date?
No. While the format is predictable, you cannot calculate someone else's license number because you would need to know the exact algorithm, and the last three digits (sequence number) are assigned by the Secretary of State and are not publicly available. License numbers are not searchable public records.