Are Gel Number Plates Legal? 3D and 4D Gel Plates Explained
Are gel number plates legal? The short answer: yes. Both 3D gel and 4D gel number plates are road legal in the UK, as long as they’re made to the current British Standard, BS AU 145e. Since 1 September 2021 raised characters have been allowed, provided they’re a single shade of solid black on a reflective white (front) or yellow (rear) plate, in the standard font and spacing, and marked with the supplier’s name and the BS AU 145e number. What makes a gel plate illegal isn’t the gel. It’s the extras some sellers add.
Written by the PlateBoss team, led by owner HD. We’ve been making plates since 2019 and are a DVLA-registered number plate supplier with a workshop in Hounslow, west London. Checked against DVLA leaflet INF104 and GOV.UK guidance on number plates, October 2026. How we write our guides.
In this guide
- What customers think
- The rules a gel plate has to meet
- What makes a gel plate illegal
- 3D gel vs 4D gel
- How long gel plates last
- FAQs
What customers think
People do ask us whether gel plates are legal, and most of them already assume they are. That’s mostly right, but only for plates made properly.
The gel plates we see that aren’t legal usually arrive with a story. The customer has failed an MOT, or been stopped and fined by the police, and needs a proper set in a hurry. The plates almost always came from an online seller, and the problem is nearly always the style: two-tone or outlined characters, a carbon effect, or a font that isn’t the standard one.
The rules a gel plate has to meet
GOV.UK and the DVLA’s leaflet INF104 set the same rules for gel plates as for any other plate fitted from 1 September 2021. The plate must:
- be made from reflective material, with black characters on white at the front and on yellow at the rear;
- have characters in a single shade of black that aren’t removable or reflective (raised 3D characters are allowed);
- use the standard font, character sizes and spacing (79mm tall characters, 11mm between characters and 33mm between the two groups on a car plate);
- have no background pattern;
- be marked with the supplier’s name and postcode and the British Standard number BS AU 145e.
Gel plates meet all of that when they’re made by a registered supplier. The raised effect comes from the gel or acrylic itself, not from shading or outlines, so it’s allowed.
What makes a gel plate illegal
- Two-tone or shaded characters. Anything that isn’t a single shade of solid black has been banned on new plates since September 2021.
- Carbon-effect, chrome, coloured or outlined letters. Same rule.
- A non-standard font, italic or “sporty” characters.
- Squeezed or moved spacing, often to make a private registration read as a word. See our guide to number plate spacing.
- No supplier name or BS AU 145e mark. Usually a sign the plate was sold as a “show plate”.
Any of these can mean a fine of up to £1,000 and an MOT fail. Our guide to show plates vs road legal plates explains why “for show use only” small print doesn’t protect you.
Want gel plates that are definitely road legal? Every set we make is solid black, BS AU 145e marked and laid out to DVLA rules.
See 4D gel platesSend us a photo on WhatsApp3D gel vs 4D gel
Both are legal, and both have a gel resin finish on top. The difference is the character underneath:
| 3D gel | 4D gel | |
|---|---|---|
| Characters | Printed, then domed with clear gel resin | Raised laser-cut acrylic, finished with gel |
| Look | Rounded, glossy, subtle depth | Taller, sharper edges, glossy finish |
| Our price | From £49.99 | From £64.99 |
At our workshop 4D gel outsells 3D gel. People like the extra depth. If you want the sharpest edges without the gel finish, our guide to whether 4D plates are legal covers plain 4D plates too.
How long gel plates last
Gel plates are durable, but they aren’t indestructible. They’re made from vinyl with a gel resin layer on top, and over many years that can deteriorate, particularly on a car that lives outside. That’s normal ageing rather than a fault.
Ours come with a 3-year warranty that covers characters coming off by themselves, peeling and fading. It doesn’t cover accident or malicious damage. Our guide to cleaning number plates helps them last longer.
Road-legal gel plates and premium styles
4D 3mm Gel Number Plates
£64.99
4D 6mm Gel Number Plates
£79.99
3D Gel Number Plates
£49.99
Bevelled Number Plates
£69.99Gel plates made properly, first time. Order before 2pm for same-day dispatch with free tracked delivery, or collect from our Hounslow workshop.
Shop number platesCollect in HounslowWhatsApp usAre gel number plates legal? FAQs
Are 4D gel number plates legal in the UK?
Yes, if they meet BS AU 145e: solid black characters in the standard font and spacing on a reflective plate, with the supplier’s name and BS AU 145e marked on it.
Are 3D gel number plates legal?
Yes. Raised characters have been allowed since 1 September 2021, as long as they’re a single shade of black and the plate meets the other rules.
Can gel plates fail an MOT?
Only if they don’t meet the rules, for example two-tone or outlined characters, the wrong font, bad spacing or missing markings. A properly made gel plate passes.
Are two-tone gel plates legal?
No. Characters must be a single shade of solid black on plates fitted from September 2021. Two-tone, carbon or outlined characters aren’t allowed.
Do gel number plates fade or crack?
They’re durable, but the vinyl and gel can deteriorate over many years. Ours have a 3-year warranty covering characters coming off, peeling and fading.
Which is better, 3D gel or 4D gel?
It’s down to looks. 4D gel has taller, sharper characters and is our more popular gel style. 3D gel has a softer, rounded look and costs a little less.
How do I know a gel plate is legal?
Look for the supplier’s name and postcode and BS AU 145e along the bottom, solid black characters and standard spacing. If those are missing, it probably isn’t.
