Short plates and hex (hexagon-ended) plates are popular on supercars, imports and cars wearing short private registrations. The good news: they can be road legal. The catch: only if nothing about the characters changes.
In this guide
The rule that matters
UK law doesn’t specify the length of a number plate. It specifies:
- the character size – 79mm tall, 50mm wide (1 and I narrower)
- the spacing – 11mm between characters, 33mm between groups
- the margins – at least 11mm of clear space around the registration
A plate can be as short as those measurements allow. What it can’t do is shrink or squash the characters to fit a smaller plate.
Short legal plates
A short registration such as “R9 LLY” or “1 ABC” leaves lots of empty plate on a standard 520mm plate. A short legal plate trims that away:
Our builder’s “Short legal – cut to fit” size calculates the shortest plate that keeps every legal measurement for your registration. There’s also a slim option at 101mm tall – the minimum height that still fits 79mm characters with 11mm margins.
Hex plates
Hex plates have angled ends, a look borrowed from Italian supercars. The angled ends are fine legally, as long as the 11mm margin around the characters stays clear of the angled cut. That means a hex plate is slightly longer than a short rectangular plate for the same registration.
What makes a short plate illegal
- ✗ Shrinking characters below 79mm on a car
- ✗ Closing up the spacing or the gap between groups
- ✗ Cutting into the margin so characters touch the edge
- ✗ Adding a badge that sits on the margin
- ✗ Missing supplier name, postcode or BS AU 145e mark
These are the plates that get stopped. Read spacing rules and illegal number plate fines.
Will a short plate pass the MOT?
A short plate that keeps all the legal measurements will pass. Testers look at character size, spacing and legibility – not plate length. Bring the plate in good, clean condition.
Do short plates suit every car?
They suit cars whose recess is smaller than a standard plate, or where a short private registration looks lost on a full-size plate. If your car has a full-width recess, a short plate can leave visible screw holes or an empty recess – a holder or surround can tidy that up.
Frequently asked questions
What’s the smallest legal number plate for a car?
It depends on the registration. A two-character registration with a 1 can be very short; the builder calculates the minimum for yours.
Are hex plates legal in the UK?
Yes, if the characters are full size, correctly spaced and the 11mm margin stays clear of the angled ends.
Can I have a badge on a short plate?
Only if there’s room for it plus the margins. The builder warns you if it won’t fit.
Are 4D short plates legal?
Yes – raised characters are allowed on any legal plate shape and size.
