Road legal number plates are not just a design choice. The size of the characters, the colour, the material and the paperwork are all set by UK law. Here is what that means when you order.
BS AU 145e
Plates fitted from 1 September 2021 must meet BS AU 145e, the British Standard for retroreflective number plates. It covers how reflective the plate is, how well the characters and the plate survive impact and weathering, and what has to be printed on the plate: the supplier name, the postcode and the standard number. Ours are made to it, and the supplier marking is printed on every plate.
Colours and characters
- Front: white reflective background, black characters.
- Rear: yellow reflective background, black characters.
- Cars: 79 mm characters, 50 mm wide with a 14 mm stroke, 11 mm spacing and margins, 33 mm between the two groups.
- Motorcycles: 64 mm characters, rear plate only.
- The legal plate font, solid black, with no italics, symbols or decorative lettering.
See the size guide for plate dimensions.
Things that make a plate illegal
- Changing the spacing to spell a word or name.
- Using italic, script or "3D style" fonts that do not match the legal character shapes.
- Coloured, tinted, mirrored or carbon-look characters or backgrounds.
- Screws, bolts, borders or badges that change how a character reads.
- Trimming or bending a plate to fit.
- A green flash on anything other than a zero-emission vehicle.
Plates that break these rules can fail an MOT and attract a fixed penalty. DVLA can also withdraw a registration that is displayed illegally.
Flags and identifiers
You can add a national flag with a matching identifier: Union flag with UK, Cross of St George with ENG, Saltire with SCO, or Welsh dragon with CYM. GB stopped being valid for driving abroad in September 2021; UK replaced it. Flags and identifiers are optional.
Documents a supplier must see
To buy road legal plates you need:
- Photo ID: driving licence or passport.
- Proof you can use the registration: V5C logbook showing the reg, a V750 or V778 certificate, or a V62 or V948.
We collect both after checkout through an upload link. It takes about a minute, and production starts once they are checked. We cannot make road legal plates without them, and there is no way around it for a DVLA registered supplier.
Fitting
Most plates go on with double-sided sticky pads. Screws work too, but they must sit in the gaps between characters, not in the characters themselves. The fitting kit in the builder includes pads, screws and caps. Clean the surface first: a plate that lifts at speed is a plate that can be lost.
Driving abroad
A UK plate with the UK identifier is accepted in the EU and most of Europe, but you still need to check the rules for the country you are visiting. Since September 2021 a GB badge on its own is not enough.
Published 24 October 2026