Road legal number plates aren’t optional when it comes to driving your vehicle. Failing to have them will result in a failed MOT and can even lead to fines. Unfortunately, thousands of UK drivers unknowingly break the rules every day. Here are the 10 most common number plate mistakes that instantly make a vehicle illegal:
1. Incorrect Spacing
The DVLA spacing rules are strict. Deviating on the gap between characters to spell a name or word more succinctly is illegal and will fail an MOT.
Changed character spacing can make it harder for ANPR cameras to read.
2. Using Non‑Standard Fonts
Only the Charles Wright font is legal for UK plates. Any other fonts are simply not allowed.
3. Tinted or Smoked Plates
Any tint that reduces reflectivity or visibility is illegal. Even light smoke finishes. There should be no changes to the plates background.
4. Incorrect Flags or Badges
Only approved national identifiers (UK, ENG, SCO, CYM, GB) are permitted on number plates. Anything else is classed as a show plate. Badges displayed over a certain distance that are off the plate remain legal. See PlatePlus for frame and badge options.
5. Wrong Material or Reflectivity
Legal plates must be made from reflective material that meets British Standard BS AU 145e.
6. Missing Supplier Details
Every road legal plate must show the supplier’s name and postcode. If yours doesn’t, it’s not legal and you should source new number plates immediately.
7. Incorrect Plate Size
Motorcycles, imports and trailers have specific size requirements. Using car‑sized plates on motorbikes is actually against the law.
8. Damaged or Cracked Plates
Even minor cracks can reduce reflectivity and cause MOT failure. So be sure to inspect your plates every so often and buy number plates from reputable sources that promote higher durability, such as Aplates.
9. Dirty or Obscured Plates
Mud, grime or snow covering your plate is treated as having no plate at all. Your registration should always be visible wherever possible.
10. Using Show Plates on the Road
Show plates are fine for events or garages but they are illegal on public roads. Always remember to change your plates back to your road legal ones in order to drive within the law.
If you want plates that are guaranteed legal, compliant and built to last, then choose a supplier who follows every DVLA requirement. Your number plates should be something you never have to worry about.