Number plates
What makes a plate legal
Checked on 7 September 2026.DVLA, INF104: vehicle registration numbers and number plates (as of 7 September 2026)
What does a legal UK number plate have to look like?
Black characters in the mandatory Charles Wright font on a reflective background, white at the front and yellow at the rear, at the published character size and spacing, with the supplier's name and postcode and the British Standard number displayed.
Plates fitted to a vehicle registered from 1 September 2021 must also meet BS AU 145e, which raised the reflectivity requirement and removed two tone and shaded characters from the specification entirely.
The measurements
| Dimension | Size |
|---|---|
| Character height | 79mm |
| Character width, except the figure 1 and the letter I | 50mm |
| Character stroke width | 14mm |
| Space between characters | 11mm |
| Space between groups | 33mm |
| Top, bottom and side margins | 11mm |
The four things that fail a plate
- Altered spacing. Moving characters so the mark reads as a name or a word is the commonest failure and the one that risks losing the registration outright.
- Non standard characters. Italic, script and any font other than Charles Wright, and any character with a shadow or an outline.
- Screws, bolts or fixings placed so they change a character. A bolt turning an F into an E is treated as misrepresenting the mark.
- Tinted, mesh or reflective covers over the plate, which are not permitted at all.
Flags and identifiers
- The left hand band may carry the Union flag, the Cross of St George, the Saltire or the Red Dragon of Wales.
- Beneath the flag the identifier may be UK, GB, ENG, ENGLAND, SCO, SCOTLAND, CYM, CYMRU, WALES or the equivalent.
- The UK identifier replaced GB for driving abroad, and a vehicle without one on the plate needs a UK sticker.
- No other badge, crest or logo is permitted in the band or anywhere else on the plate.
Are 3D and 4D plates worth the risk?
A raised gel 3D plate can be legal if the characters keep to the specification and the plate meets the reflectivity standard. Layered 4D acrylic characters usually do not, because the shadow they cast changes how a camera reads them, and that is what a roadside check looks at.
Common questions
- Are 3D and 4D number plates legal?
- A raised or 3D gel plate can be legal if the characters still meet the specification and the plate passes the reflectivity standard. Layered 4D acrylic characters are the ones that fail most often, because the shadow they cast changes how a camera reads the character.
- Can I change the spacing to make my plate read as a word?
- No. Character and group spacing are fixed by regulation, and altering them so a mark reads as something else is the commonest reason a plate fails. It also makes the plate an offence to display and can cost you the registration itself.
- Which flags are allowed on a number plate?
- The Union flag, the Cross of St George, the Cross of St Andrew or Saltire, and the Red Dragon of Wales, each with the appropriate national identifier beneath it. Anything else on the left hand band is not permitted.
- What happens if my plate is not legal?
- You can be fined up to £1,000 and the plate will fail a roadworthiness inspection. If the mark has been misrepresented, DVLA can also withdraw the registration, which is the expensive outcome for anybody who paid for a private plate.