If you've been shopping for number plates, you've probably seen "BS AU 145e compliant" mentioned repeatedly. But what does it actually mean, and why should you care?
What is BS AU 145e?
BS AU 145e is the current British Standard for road legal number plates in the UK. It sets out the technical requirements that all number plates must meet to be legal for use on public roads. The "e" at the end indicates it's the fifth revision of the standard — replacing the previous BS AU 145d — and it came into force in September 2021.
What does it cover?
BS AU 145e covers a wide range of technical requirements, including:
- Reflectivity — plates must reflect enough light to be readable at night and in low visibility conditions.
- Colour — front plates must be white, rear plates must be yellow, with black characters.
- Font — the Charles Wright font must be used. Characters cannot be altered, styled, or modified in any way that makes them harder to read.
- Character size and spacing — character height, width, stroke thickness and spacing between letters and numbers are all precisely defined.
- Near-infrared reflectance — plates must be readable by ANPR cameras used by police and local authorities.
- Manufacturer markings — every plate must display the name and postcode of the supplier and the BS AU 145e standard number.
Why does it matter?
Driving with non-compliant number plates is illegal and can result in a fine of up to £1,000. Non-compliant plates can also fail an MOT, invalidate your insurance, and prevent ANPR cameras from reading your registration correctly. More practically — if your plates aren't BS AU 145e compliant, you're at risk every time you drive.
How do you know if your plates are compliant?
The simplest way is to buy from a DVLA-registered supplier who explicitly confirms BS AU 145e compliance. Every plate we produce at Paramount Plates meets the standard and carries the required manufacturer markings.
If you're unsure about plates you already have, check for the BS AU 145e marking printed on the plate itself — it's required by law and should be visible at the bottom of the plate.
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