Short number plates are popular on imports, classic cars, motorbike-style recesses and anything where a full-size plate looks oversized. But "how short can I go?" doesn't have a single answer – because the law doesn't set a plate length. It sets the size of the characters and the space around them.
What the rules actually say
The DVLA's display rules fix the characters, not the plate:
- Every character is 79mm tall and 50mm wide (the number 1 and the letter I are narrower).
- There's 11mm between characters and 33mm between the two groups.
- There must be at least 11mm of clear margin around the characters – top, bottom and both sides.
So the shortest legal plate is simply the width your registration needs at full size, plus the margins. A standard 520mm plate is just a size that fits every current registration comfortably.
Working it out for your registration
Add up the characters, the gaps and the margins:
- "RG 24" – four 50mm characters, two 11mm gaps, one 33mm group gap and two 11mm margins: about 277mm wide.
- "AB12 CDE" – six full-width characters, a narrower "1", five character gaps, a group gap and the margins: about 424mm wide.
- A full current-style registration without a 1 or I needs about 460mm.
Height works the same way: 79mm characters plus 11mm top and bottom gives a minimum of 101mm.
What about 14", 16" and 18.5" plates?
Fixed sizes like 14" (356mm), 16" (406mm) and 18.5" (470mm) are common, but whether they're legal depends on your registration:
- Short dateless and private registrations often fit a 14" or 16" plate legally.
- Most full current-style registrations won't fit a 14" or 16" plate without shrinking the characters.
- An 18.5" plate fits every 7-character registration at full size – it's the shortest fixed size that always works. (A true 18" plate, at 457mm, is 3mm too short for a 7-character registration without a 1 or I.)
If the characters have to be made smaller to fit, the plate is a show plate and must not be used on the road.
Adding a UK flag
The UK national identifier sits on the left of the plate and needs roughly 50mm of extra width. Factor that in if you want a flag on a short plate.
The easy way: let the builder work it out
Our number plate builder calculates the minimum legal size for your exact registration. Choose Shortest legal fit and the plate is cut to exactly 11mm clear all the way round. Each fixed size is labelled either "Legal-size characters" or "Show plate only", so you know before you order.
Read more about short number plates or the full road legal guide.