# UK Number Plate Rules: What Makes a Plate Legal

Published 27 September 2026. CarCheckUp guide: https://carcheckup.co.uk/blog/uk-number-plate-rules-what-makes-a-plate-legal/

> Number plates in the UK have strict rules on font, spacing, colours and where they come from. Here is what makes a plate legal and what happens if yours isn't.

Number plates aren't just decoration: they identify your vehicle to the police, cameras and other drivers. The rules are strict, and plates that break them can mean a fine and an MOT failure.

## What a legal plate must have

- **The British Standard:** plates fitted since 1 September 2021 must meet British Standard BS AU 145e, marked on the plate.
- **The right font:** the standard “Charles Wright” typeface. Italic, stylised or 3D fonts that change the shape of characters aren't allowed; raised (3D) characters are allowed if they are black and meet the standard.
- **Correct spacing and size:** characters must be the standard size and spacing. Moving spaces or using screws to change how letters look is illegal.
- **Colours:** black characters on a white plate at the front, and on a yellow plate at the back.
- **Supplier details:** the name and postcode of the supplier who made the plate.

You can also show a national identifier on the left, such as the UK identifier, and some flags. Plates must be clean and readable at all times.

## Buying number plates

Plates must be made by a supplier registered with DVLA. They must ask for proof of your identity and proof that you're entitled to the registration, such as the V5C. A seller who makes plates without asking for anything is breaking the rules, and it's one way criminals get plates for [cloned cars](https://carcheckup.co.uk/blog/cloned-cars-uk-how-a-vin-check-protects-you/).

## What happens if your plates are illegal

- You can be fined up to £1,000.
- The car will fail its MOT.
- DVLA can withdraw a private registration number that is displayed illegally.

## Private plates and plate changes

A private plate moved onto or off a car creates a [plate change](https://carcheckup.co.uk/dvla-number-plate-change-history) on its record. That's normally innocent, but it can separate a car from its history, so it's worth checking when buying. Our guide on [plate change history](https://carcheckup.co.uk/blog/check-vehicle-plate-change-history-for-free-guide-in-the-uk/) explains more, and [when to replace your plates](https://carcheckup.co.uk/blog/key-reasons-for-replacing-your-number-plates/).

## Checking the plate matches the car

When buying, check the plates match the registration on the V5C, and that the make, model and colour on record match the car. A free [reg plate check](https://carcheckup.co.uk/car-reg-plate-check) shows the vehicle details held for any registration.

## Key points

- Plates must meet the British Standard, use the standard font and spacing, and show the supplier.
- Illegal plates can mean a fine of up to £1,000 and an MOT failure.
- Buy plates only from a registered supplier with your V5C.

To see what the DVLA holds for a plate, run a **number plate check**. Our free [car reg check](https://carcheckup.co.uk/car-reg-plate-check) works as a **reg plate check** for any UK registration and shows the make, model, colour, tax and MOT status recorded for it.