How Does The GB Number Plate System Work?

How does the UK licence plate system work, and what do all the letters and numbers mean? We show you how to decode the number plate system and also how to determine the age of the vehicle just by reading the number plate.

We’ll be covering the standard number plate and not personalised number plates that you may come across.

What are the different components of the number plate?

The current format for vehicle registration numbers was introduced on 1 September 2001 for all new vehicles being registered. The format is two letters, two numbers, a space and a string of three letters for the whole of Great Britain.

Number plate

The first two letters are the DVLA memory tag, the two numbers (the age identifier) indicate the age of the vehicle, and the last three letters are random.

Northern Ireland registrations have their own format, 1, 2, 3 or 4 numbers, paired with a block of letters that always contain an I or Z. The letter combinations work as an original area-identifier; for example, Enniskillen was originally allocated “IL” marks.

The DVLA memory tag:

The first two letters are called a ‘memory tag’, which is a location identifier for where the car is first registered. While this used to be determined by the DVLA office where the registration took place, however, the DVLA closed all its regional offices at the end of 2013 and now handles new registrations directly with car dealerships through an online system.

Other regions of England have their own letter codes; Reading-registered cars start with the letter R, Essex-registered cars start with an E, and so on. For example, if you’re buying a new car in Scotland, it will almost certainly start with an S. For cars registered in Wales, it will start with a C for Cymru.

The age identifier:

The two numbers are called the ‘age identifier’, which tells you in which six-month period the car was first registered.

The numbers change every six months, in March and September. The March codes are easy to remember as they follow the year of registration. For cars registered between September and February, it changes. The numeric code equals the year (as of September) plus 50.  So a car registered from September 2021 until February 2022 will have the number 71 (= 21 + 50). A car registered in September 2006 – February 2007 has the number 56 (=06 + 50), and so on. This pattern will continue until all possible variations are used.

The last three letters:

They’re really just random letters. However, due to batch allocation of new registration marks to dealers, it is common for cars with “neighbouring” letter sequences to be of the same manufacturer.

And that’s how you can find out the car’s age:

As you may have guessed by this point, you can find a car’s age using the third and fourth digits of the new number plates. They will either be the last two digits of the release year (16 for cars released March 2016, for example) or the last two digits plus 50 for cars released in September (66 for cars released in September 2016).

Other identifiers: 

It is not mandatory to have this but some cars have a green band on the left. This is a new initiative for zero-emission cars so most EVs will have this on the number plate to help easy identification of electric cars for the purpose of cheaper parking, etc.

Fun fact 1: When you change cars, you can keep your number plate. You need to do this BEFORE you sell your old car by filling out a V317 form and paying a fee to the DVLA.

Fun fact 2: If you ever need a repair or car service, you only need to enter your vehicle registration number along with your postcode and get an instant fixed price in seconds for a repair or service you need – it’s that simple! Head to our website and a trusted mechanic can carry out a repair or service at your choice of time and date.

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