Your customer identifier is a unique number your state assigns to track your license record

The customer identifier (sometimes called a customer ID or document number) is a number printed on your driver's license that belongs only to you in your state's licensing system. It is not the same as your license number, your Social Security number, or your date of birth. Think of it as an internal filing number — the DMV uses it to pull up your exact record when you renew, update your address, or check your driving history.

Every state has a customer identifier system, though the name and format vary slightly. Some states call it a "document number," others a "customer reference number," and a few print it alongside other identifiers on the card itself. The number stays the same throughout your life in that state, even if you renew your license multiple times or change your name.

You will see this number printed somewhere on your physical license card — usually on the back or in a corner of the front. It is a practical tool for the DMV, but you rarely need to memorize it or use it yourself unless you are calling the DMV to check on a record or dispute something on your file.

Key Takeaways

  • Your customer identifier is a unique number assigned by your state's DMV to track your individual license record in their system.
  • The number stays the same for life in that state, even if you renew your license or change your name.
  • You can find your customer identifier printed on your physical license card, usually on the back or in a corner.
  • You may need to provide this number when calling the DMV to look up your record, check your driving history, or resolve an issue with your account.

Where to find your customer identifier on your license

The location of your customer identifier varies by state. In many states, it appears on the back of the card in small print, sometimes labeled as "Document #," "Customer ID," or "Reference #." In others, it may be on the front near your name or license number. Check the back first — that is the most common placement.

If you cannot find it on your physical card, you can also look it up online through your state's DMV website. Most states allow you to log into a driver portal or search tool using your license number and date of birth, and the system will display your customer identifier. You can also call your state DMV directly and provide your name and date of birth, and they will give you the number over the phone.

When you need to use your customer identifier

In most cases, you will not need your customer identifier for everyday driving. You do not provide it to police during a traffic stop, and you do not need it to show proof of insurance or registration. It is an internal DMV tool.

You may need it if you are calling the DMV to check on the status of a license renewal, dispute something on your record, look up your driving history, or resolve an issue with your account. Having the number ready speeds up the process because the DMV staff member can pull your file when ready instead of searching by name and date of birth. If you are explore for a job that requires a background check or a professional license that requires a driving record, the organization may ask for your customer identifier to verify your information quickly.

How your customer identifier differs from your license number

Your license number is the main identifier printed prominently on the front of your card — it is what police and other officials use to look up your record. Your customer identifier is a separate number used only within the DMV's internal system. If you move to a new state and get a new license, you will get a new license number, but your customer identifier only exists in the state that issued it.

Think of it this way: your license number is your public ID for driving purposes, while your customer identifier is your private file number within that state's DMV database. You will use your license number far more often in your daily life.

What happens to your customer identifier if you renew or replace your license

Your customer identifier stays the same every time you renew your license, even if your license number changes. This is by design — the DMV wants to keep your entire driving history linked to one permanent identifier, so they can track your record over decades and multiple renewals.

If you replace your license because it was lost, stolen, or damaged, you will get a new license number but keep the same customer identifier. The same applies if you change your name due to marriage or legal change — your customer identifier remains constant, and your driving history stays attached to it.

Protecting your customer identifier

Your customer identifier is not as sensitive as your Social Security number, but you should still treat it as personal information. Do not share it casually or post it online. If someone asks for it, verify that they are actually from your state's DMV or a legitimate organization that needs it for a valid reason.

If you suspect someone has misused your customer identifier or accessed your DMV record without permission, contact your state's DMV when ready. You can also place a fraud alert with the credit bureaus if you believe your identity has been compromised.

Frequently Asked Questions

Is my customer identifier the same as my license number?

No. Your license number is the main identifier on the front of your card and is used by police and officials. Your customer identifier is a separate internal number the DMV uses to track your file. If you renew or replace your license, your license number may change, but your customer identifier will not.

Do I need to memorize my customer identifier?

No. You only need it if you are calling the DMV to look up your record or resolve an issue. You can find it on your physical card or look it up online through your state's DMV portal anytime you need it.

What if I move to a different state?

Your customer identifier only exists in the state that issued it. When you get a license in a new state, you will receive a new customer identifier for that state's system. Your old identifier remains in your previous state's records.

Can I change my customer identifier?

No. Your customer identifier is assigned by the DMV and cannot be changed. It is tied to your record for life in that state, even if you renew multiple times or change your name.

Why does the DMV need a customer identifier if they already have my license number?

The customer identifier allows the DMV to track your complete driving history across multiple license renewals and changes. Your license number may change over time, but your customer identifier stays constant, keeping all your records linked together in their system.