The plate can't be read properly, isn't the correct format, or isn't securely attached. Faded, cracked or peeling plates are the most common version; novelty spacing and non-standard fonts are the next.
Wording as it commonly appears on an MOT certificate: “Registration plate insecure, illegible or incorrectly formatted”.
What does it mean?
The plate can't be read properly, isn't the correct format, or isn't securely attached. Faded, cracked or peeling plates are the most common version; novelty spacing and non-standard fonts are the next.
How serious is it?
Usually recorded as: Major. The tester assesses the actual vehicle on the day, so your certificate is what counts.
What normally causes it?
- UV fading and delamination on older plates — very common on rear plates
- Cracks from over-tightened screws
- Non-standard spacing or fonts fitted to make the registration read as a word or name
- A plate hanging loose because the pads or fixings have failed
What a mechanic would check
Stand back and read it. If the characters have gone grey or the layer is lifting, it needs replacing. Spacing and font are measured against the standard, so anything creative will fail no matter how long it's been on the car.
What might need replacing
- A correctly formatted replacement plate
- New fixings or sticky pads
Can you still drive it?
It's a failure item and also an offence — an illegible or misspaced plate can attract a fine and, at worst, the registration being withdrawn. It's also one of the cheapest and quickest things to put right.
Repair cost
A pair of standard plates is one of the cheapest items on any MOT bill. You'll need to show your V5C or other proof of entitlement when ordering.
Before the retest
Plates must be made by a registered number plate supplier in the correct characters, spacing and font, with no stylised letters, badges outside the permitted ones or covers. Check they are firmly fixed, clean and readable from a sensible distance, and that the rear plate lamp works. Bring your V5C if you order new plates, because the supplier will ask for it.
Retest rules
If the vehicle stays at the test centre for repair and is retested within 10 working days, a partial retest is often free; some items qualify for a free retest if you bring the car back by the end of the next working day. The exact conditions are set out on GOV.UK, so confirm with the test centre before you leave. A major or dangerous failure means the car cannot legally be driven away unless the previous MOT is still valid and nothing dangerous was recorded — check your certificate first.
Related help
More registration plates and vin failures · MOT failure decoder · Ask a mechanic about your certificate
This is general guidance from a UK mechanic, not a substitute for a physical inspection. Only the tester who inspected your vehicle can confirm what was recorded and why.