Skip advert
Advertisement
Tips & advice

What are 4D number plates and are they legal?

Everything you need to know about so-called ‘4D’ number plates, including whether you’re allowed to have them on your car

Having a valid set of number plates is one of many requirements for legally driving your car on the road. Many drivers will purchase a personalised registration number in a bid to brighten up this rather dull fact of life, and some motorists are now following a new trend of fitting what have become known as ‘4D’ number plates.

These increasingly common plates feature raised lettering that stands out more from the background of the plate. Despite their popularity, however, more and more incidents of police stopping vehicles with these types of number plates have been reported, particularly on social media. This has led drivers to question what the rules are on what at first appears to be a grey area.

What are the rules for number plates?

In the UK, number plates have to meet the following criteria set out by the Driver and Vehicle Licensing Agency (DVLA):

Advertisement - Article continues below
  • Number plates must be made from a reflective material
  • Number plates must display black characters on a white background at the front and black characters on a yellow background at the rear
  • Number plates must not have a background pattern
  • Number plates must be marked to show who supplied the number plate
  • Number plates must be marked with a British Standard number - this is ‘BS AU 145e’ for plates fitted after 1 September 2021
Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

There are also strict rules governing the size and shape of the letters on a number plate. These must be printed in Charles Wright font, with characters 79mm in height, 50mm in width and with a space between them of 11mm.

The DVLA also states that, in addition to having a choice of national identifier for the strip on the left-hand side of the number plate, drivers can choose to have what it describes as “3D (raised) characters”.

Are 4D number plates allowed?

In spite of the DVLA specifically stating that number plates can have raised lettering, the rules are more complex in reality.

As Sergeant Dan Pascoe from Surrey Road Policing Unit explained to us, although there is no law against a number plate having raised lettering in itself, the characters can’t stick out so much as to obscure the registration from being legible from an angle.

Another issue with so-called ‘4D’ plates is that the characters aren’t always built into the structure of the number plate and are instead stuck on with adhesive. This means they can actually fall off over time, leaving the driver with an incomplete, and therefore illegal, plate.

As such, the advice is for drivers to stay on the safe side and stick with conventional 2D number plates.

More on car number plates...

Skip advert
Advertisement
Skip advert
Advertisement

Recommended

Pavement parking explained: is it illegal to park on the pavement?
Ford Fiesta parked on pavement

Pavement parking explained: is it illegal to park on the pavement?

Parking on the pavement is illegal in London and Scotland, but it’s a grey area for the rest of the UK. We explain the do’s and don’ts
Tips & advice
24 Jul 2026
Best car bug cleaner 2026
Bug remover - header image

Best car bug cleaner 2026

Dead bugs are the bane of your life if you like to keep your car looking perfect in summer. That’s why a good remover is vital
Product group tests
1 Jun 2026
Aftermarket parts can transform a used car bargain
Opinion - aftermarket car parts

Aftermarket parts can transform a used car bargain

Auto Express’s deputy editor reckons it’s worth sprucing up your next car with a few choice aftermarket accessories to get the exact look you’re after
Opinion
28 May 2026
Fuel duty freeze extended until at least the end of 2026
Diesel pump

Fuel duty freeze extended until at least the end of 2026

The 5p cut to fuel duty won’t be unwound in September, as had previously been announced
News
20 May 2026

Most Popular

New Peugeot 308 to get radical fastback looks
Peugeot 308 Fastback render - front 3_4 Avarvarii

New Peugeot 308 to get radical fastback looks

Peugeot knows buyers are moving from hatchbacks to SUVs, so it’s considering a very different look for the 308
News
17 Aug 2026
Car Deal of the Day: Volvo XC40 is a practical family SUV for under £300 a month
Volvo XC40 - front full width

Car Deal of the Day: Volvo XC40 is a practical family SUV for under £300 a month

A Volvo XC40 still offers plenty of style and panache despite its advancing years. It’s our Deal of the Day for 17 August.
News
17 Aug 2026
Rivian is coming to the UK, and here's how it could topple Tesla
Rivian is coming to Europe - R2 front tracking

Rivian is coming to the UK, and here's how it could topple Tesla

Rivian CEO reveals the brand’s Tesla Model Y rival was developed with Europe in mind
News
17 Aug 2026

Find a car with the experts