11-Digit V5C Number: Where It Is on Your Logbook

By Matthew Croxford · 12 Aug 2026 · Updated 20 Oct 2026

Short answer: The 11-digit V5C number is in a labelled box towards the top right of the front page of your logbook, with no letters. Don't confuse it with the serial number in the small circle on the top left, which is two letters followed by seven numbers and won't work in online services. If lost, it can't be looked up online.

Short answer: the 11-digit number is in a labelled box towards the top right of the front page of your V5C logbook. It has no letters, and it is the number DVLA means when a service asks for your document reference number. If you have lost the logbook, you cannot look the number up online.

If you have tried to tax your car or tell DVLA you have sold it, you will have been asked for the 11-digit reference number from your V5C. It is one of the most searched things about the logbook, and one of the easiest to get wrong, because the V5C has more than one number on it.

Where is the 11-digit number on a V5C?

It is on the front page of your V5C, in a clearly labelled box towards the top right. It is 11 digits long, with no letters.

Do not confuse it with the serial number in the small circle on the top left, which is two letters followed by seven numbers. That one identifies the piece of paper, not your vehicle record, and it will not work in any online service.

What is the 11-digit V5C number used for?

It is the code behind most everyday DVLA jobs: taxing the car, declaring it off the road (SORN), telling DVLA you have sold or transferred it, and updating your details. Type it exactly as printed. A single wrong digit is the most common reason people get bounced out of the tax screen, so check it carefully before assuming something is broken.

Which reference numbers do people mix up with it?

Three different documents each carry their own reference number, and they are not interchangeable:

V5C logbook - the 11-digit number, if you are the keeper and have the logbook.
V11 tax reminder - the reference number printed on the reminder letter, if it has arrived but the logbook has not.
Green new keeper slip (V5C/2) - a 12-digit number. Just bought the car and your V5C has not arrived yet? Use this to tax it now, then switch to the 11-digit number once your logbook lands.

What if I have lost my V5C?

The 11-digit number is only printed on the physical logbook, so there is no way to look it up online. If yours is lost or damaged and you are the registered keeper with no change of details, you can apply for a replacement online for £25. If your details have changed, you apply by post on a V62 form instead. To tax the car in the meantime, use the reference number from a V11 reminder, or the 12-digit number from the new keeper slip if you have just bought it.

Buying or selling? Check the record first

Before money changes hands on a used car, it is worth a quick look at the basics. The free reg check on MotifyMe® pulls up the car's key DVLA details, including MOT and tax status, in a couple of seconds, so you can sanity-check what the seller tells you. And if you are selling, tell DVLA using your 11-digit number and hand over the green slip on the day, because until the record updates you are still the keeper on paper.

Frequently asked questions

How many digits is the V5C reference number? It is 11 digits long, with no letters, and it is printed in a labelled box towards the top right of the front page of the logbook.

Is the 11-digit number the same as the V5C serial number? No. The serial number is in the small circle on the top left, is two letters followed by seven numbers, and will not work in online services.

Can I find my V5C number online? No. The number is only printed on the physical logbook, so if you have lost it you need to apply for a replacement V5C.

Can I tax my car without the 11-digit number? Yes, in some cases. Use the reference number from a V11 tax reminder, or the 12-digit number from the green new keeper slip if you have just bought the car.