Are 4D Plates Legal?
Are 4D Number Plates Legal in the UK?
Yes — 4D number plates are fully road legal in the UK, provided they’re made to the current British Standard, BS AU 145e. The style itself isn’t the issue; it’s how the plate is made that determines whether it’s legal.
What Makes a 4D Plate Road Legal
Under BS AU 145e, every number plate — flat printed, 3D gel, or 4D — must meet the same core requirements:
✔ Solid black characters (no colour, tint, or clear sections)
✔ Charles Wright font — the only DVLA-approved typeface
✔ Character height of 79mm, width of 50mm, stroke width of 14mm
✔ Minimum spacing of 11mm between characters, 33mm between groups
✔ Front plates on a white reflective background, rear plates on yellow
✔ Manufacturer’s name/trademark and the BS AU 145e mark shown on the plate
A 4D plate meets all of these in exactly the same way a standard printed plate does — the raised acrylic characters are simply moulded and finished in solid black, so they’re legal as long as the shaping process doesn’t affect the character dimensions or introduce colour into the letters.
Where 4D Plates Can Become Illegal
The issue is never the 4D style itself — it’s when suppliers cut corners on the standard. 4D plates can fail the legal requirements if they have:
✘ Characters that are coloured, tinted, or partially clear
✘ Spacing that’s been “squeezed” to fit a shorter registration
✘ Missing supplier details or British Standard number
✘ Non-reflective or incorrectly coloured backing
These are the plates that get flagged by ANPR cameras and can result in an MOT failure or a fine — not the 4D finish itself.
Has There Been a Ban on 4D Plates?
No formal ban on 4D or 3D gel plates has been announced. What’s being enforced more strictly is action against deliberately non-compliant plates — those with tints, ghost effects, squeezed spacing, or missing markings. A genuine BS AU 145e-compliant 4D plate from an authorised supplier remains fully legal.
Buying 4D Plates You Know Are Legal
The simplest way to make sure your 4D plates are road legal is to buy from a DVLA-authorised supplier who manufactures to BS AU 145e as standard. Every 4D plate we make at PlateBoss is solid black, correctly spaced, and stamped with our supplier details — so it’s ANPR-readable and MOT-safe from the day it arrives.
Explore our 4D Number Plates range or see how they compare to our 3D gel plates.
