What's in a number plate? Quite a lot, actually. 

Car number plates give information about the age of a car, the area it's from, and, since 2020, its fuel type. With modern car design becoming even more outlandish, only one design feature stays constant: the number plate.  

Today, we're exploring all-things-number-plates. This blog has the lowdown you need, from UK number plate area codes and personalised plates to legalities and what green plates mean. Scroll down to get informed now.  

The UK number plate format explained 

UK registration plates have evolved over the years. But the current style has been in place since 2001. This is how it's broken down: 

1. UK number plate area codes 

The first two letters are used to identify where the car was first registered. The first letter denotes the region, typically in a mnemonic style e.g. E = Essex, but not always.  

The second letter is allocated randomly to registration offices within that area. If you’re interested the chart can be found here.  

Or you can see a few examples of the UK number plate area codes below: 

2. UK number plate year codes (age identifier) 

The two numbers that follow the registration plate area codes are the UK number plate year codes (also known as age identifiers). These show the age of the car down to the six month period. Age identifiers change every March 1st and September 1st.  

For example, cars bought from 1st March to August in 2021/22 have an age identifier of 21 and cars bought from 1st September to February in 2021/22 have an identifier of 71.  

See the table below to see how the UK number plate year codes work: 

3. Random letters  

Finally, random letters are then added to the number plate to give it a unique identity. These don’t have any meaning.  

How to calculate a car's age from the UK number plate year code 

New UK number plate year codes are issued twice yearly. The second number indicates the year, and the first indicates what half of the year the reg was issued. The numbers used as the year refer to the unit of the year, e.g. BD51 = 2001, but this becomes less straightforward as the years go on. 

A detailed breakdown can be found here. 

The first two numbers denote the age of the registration number but not necessarily the car. Although, in most cases, you can tell how old a car is from its number plate, it is not always a sure thing.    

For example, a car with “70” in its number plate is from September to February 2020/21. 

Older number plates  

Before 2001, the number plates followed a ‘Prefix’ style where the characters followed the format of one letter, three numbers, and then three letters.  

In the Prefix format, the age is denoted by the first letter, ranging from A (1983) to X (2000), with only one new registration released yearly.  

Like the modern format, the first two letters of the last group give the area where the registration was first made.  

Why are some UK number plates green? 

Some number plates are green because they’re on an electric vehicle. This format has been around since December 2020.  

Green number plates are only allowed on full EVs, and their purpose is to make spotting cars wrongly parked in EV-only spots easier. It also identifies the vehicle quickly for zero congestion or ULEZ charges. 

Quick guide to personalised number plates  

Personalised number plates (also known as ‘Cherished Plates’) allow people to personalise their car by including their initials, age, and other personal touches.  

Here are some common questions about personalised registration plates.  

Where can I buy a personalised number plate?  

There are a few ways to buy personalised plates, the best place to start is the DVLA plate auction, but there are quite a few other private websites where you can search for certain sets of characters.   

Prices start at around £200 and can soar into the millions.   

Can I keep my own number plate?  

Many ‘personalised’ plates are just standard format number plates with special meanings. So, if your number plate contains your initials or means something to you, you can remove the number from the car to put it on another.  

There are a few requirements for this, including how old the car is and how long it has been on the road, but they are all laid out here. 

Are personalised plates legal?  

Yes, but you have to follow the same rules for spacing and format as other plates.   

One fundamental rule is that you cannot make a car appear newer than it really is by fitting a more modern registration plate.  

Your plates will be rejected if your desired personalised plate doesn't fit the format. 

Number plates and the law  

Because number plates are used for identification, they need to be easy to read by both humans and ANPR systems. Your plates must meet specific guidelines, or they won’t be deemed road-worthy. 

Number plate letter size and spacing  

The standard car number plate needs to have 79mm tall and 50mm wide characters. The spacing between letters should be at a minimum of 14mm.   

One trend that these requirements aim to curtail is placing letters close to one another to create a different spelling. Doing this will incur a £1,000 fine and 3 points.  

There are also strict requirements on letter font and colour. Deviation from the standards set out by the DVLA is not allowed.  

Are number plate borders legal?  

You may have noticed some number plates have a coloured border around them. This was technically illegal before 2020.  

After 2020, new legislation has made number plate borders legal as long as they follow specific criteria: 

• They are permanent  
• They are non-reflective  
• They are one shade with no fading or patterns  
• Their letter size follows the specification  

What flag can I have on my number plate?  

In 2009, the rules changed for national identity flags on number plates. Cars registered in the UK can display a flag of England, Scotland, Wales, or the Union Flag.   

Abbreviations of the country names are also allowed but only under a specific guideline, such as “GB”, “Sco”, etc. The complete list is found here. 

The European flag surrounding the “GB” wording is also still permitted. This is because it removes the need to display a separate “GB” sticker on your car should you travel to Europe. 

What are Q plates?  

Q plates are used on vehicles with either a classified or unknown history. These plates present no information regarding age or location.  

They are often seen on kit, agricultural, and imported cars. In these instances, a Q plate may be used as the vehicle's exact manufacture date is unknown, or they do not have a Vehicle Identification Number.  

Other vehicles often fitted with Q plates are ex-military vehicles that cannot have their history released.  

All about UK number plates - The bottom line 

Though they usually go unnoticed, registration plates tell you a lot about your vehicle. Hopefully, this guide has helped you tell your UK number plate year codes from your area codes. Don’t forget this information when you need to workout when and where you purchased your car! 

Work with an expert 

Need help covering car repairs and surprise costs? Bumper is here to help you split bills into interest-free monthly payments. We’re also on hand to assist with finding local garages and dealerships because we believe car maintenance shouldn’t be stressful! 

Author - Joseph Law

Joseph has been writing about cars for over seven years and writing for Bumper for over two, blending his passion for automobiles with a talent for storytelling.

Joseph has written about engineering and cars for Autozilla, Komaspec, and several engineering manufacturers. When he's not writing or tinkering with one of his five cars, Joseph dreams of owning an Alfa Romeo 33 Stradale.