Motorbike Number Plate Size: UK Rules, Dimensions and Small Plates
Short answer: there’s no fixed motorbike number plate size in UK law. What the law fixes is the size of the characters: on bikes registered from 1 September 2001 they must be 64mm tall and 44mm wide, set on two lines, with set spacing and margins around them. For a standard 7-character reg, that makes the smallest legal plate about 9 x 7 inches (229 x 178mm). The plate goes on the back only.
It’s the question every rider asks at the counter, usually followed by “can you make it smaller?”. Here’s exactly how small you can go, and where it stops being legal.
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 and GOV.UK guidance, September 2026. How we write our guides.
In this guide
- Motorbike number plate size: the rules
- Why most bike plates are 9 x 7 inches
- Are small motorbike plates legal?
- Bikes registered before September 2001
- Flags, 3D/4D and electric bikes
- What happens if your plate isn’t legal
- FAQs
Motorbike number plate size: the rules
For motorbikes, mopeds and scooters registered on or after 1 September 2001:
| Rule | Requirement |
|---|---|
| Which plates | Rear only |
| Layout | Two lines (age identifier on top, random letters below) |
| Character height | 64mm |
| Character width | 44mm (except the number 1 and the letter I) |
| Stroke (thickness of the black) | 10mm |
| Space between characters | 10mm |
| Space between the two lines | 13mm |
| Margins | At least 11mm top, bottom and sides |
| Font | Charles Wright |
| Colours | Black characters on a reflective yellow background |
| Markings | Supplier’s name and postcode, and BS AU 145e |
Motorcycle registrations issued since 1973 have to be on two lines, so a one-line “car-style” plate on a bike isn’t legal.
Why most motorbike plates are 9 x 7 inches
Do the maths on a standard reg like AB12 CDE and you get the answer:
- Width: the top line has 4 characters (4 x 44mm) plus 3 gaps (3 x 10mm) plus two 11mm margins. That’s about 228mm.
- Height: two lines of 64mm characters, the 13mm gap between them, and two 11mm margins. That’s about 163mm, so most plates round up to 178mm (7 inches).
That’s why 229 x 178mm (9 x 7 inches) is the standard motorbike plate. It’s not a size someone chose. It’s the smallest plate that fits a normal reg at the legal size.
Need a legal bike plate? We make standard printed plates for bikes registered from September 2001, to the exact legal size and spacing, £19.99 with free tracked delivery.
Order a motorbike plateAsk us on WhatsAppAre small motorbike number plates legal?
Only if the characters and spacing stay at the legal size. There’s no minimum plate size written in law, but there is a minimum character size, so the plate can only be as small as the characters allow.
- Legal: a smaller plate for a shorter reg. A private plate with fewer characters needs less room, so it can legally be smaller than 9 x 7 inches.
- Not legal: shrinking the characters, squeezing the gaps or trimming the margins so a normal reg fits on a “stubby” or “mini” plate. However neat it looks on a sports bike, it’s a show plate.
We get asked for tiny bike plates all the time at the workshop, and the answer is always the same: we can’t make them, because they’re not road legal. Those plates are sold online all the time, usually with no documents asked for. We explain how to spot them in our guide to show plates vs road-legal plates.
Bikes registered before 1 September 2001
Older bikes can display a front plate as well as the rear one, but they don’t have to. They can also use the older character sizes. The DVLA sets out two options for plates on vehicles from before 1 September 2001:
| Group 1 | Group 2 | |
|---|---|---|
| Character height | 89mm | 79mm |
| Character width (except 1 and I) | 64mm | 57mm |
| Stroke | 16mm | 14mm |
| Space between characters | 13mm | 11mm |
| Space between groups | 38mm | 33mm |
| Margins (minimum) | 13mm | 11mm |
| Space between the two lines | 19mm | 19mm |
These bigger characters mean a bigger plate than the modern 9 x 7 inch size. Please note: at PlateBoss we make plates for bikes registered on or after 1 September 2001 only. We don’t make plates for older bikes.
Classic bikes built before 1 January 1973 can also display traditional black and silver plates.
Flags, 3D/4D plates and electric bikes
- Flags and identifiers: the same rules as cars. You can have the Union flag, Cross of St George, Cross of St Andrew or Red Dragon of Wales with an approved identifier such as UK, on the left of the plate.
- 3D and 4D: raised characters are allowed in law if they’re solid black, in the legal font and size, and the plate meets BS AU 145e. For bikes, we make standard printed plates only. They’re the most practical option on a bike, where the plate takes vibration, spray and the odd knock. More on raised plates in are 4D plates legal?
- Electric motorbikes: zero-emission bikes can display the green flash on the left of the plate.
For the full rules on all vehicles, see our guide to road-legal number plates.
What happens if your motorbike plate isn’t legal?
- A fine of up to £1,000 for an incorrectly displayed plate.
- An MOT fail. Testers check the plate’s size, characters, spacing and condition.
- Easier to get noticed by police and ANPR cameras, especially with a bent or tilted plate.
Bike plates take a beating from vibration and the weather, so check yours isn’t cracked, faded or bent. To order a replacement you’ll need your ID and V5C. Here are the documents needed for number plates. And our fitting guide covers screws and pads.
Your bike plate, fitting kit, and plates for your car
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Motorbike Number Plate
Original price was: £30.00.£19.99Current price is: £19.99.
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Extra Strong Adhesive Pads (8 in a pack)
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3D Gel Number Plates
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4D 3mm Number Plates
Original price was: £70.00.£49.99Current price is: £49.99.Ready to order your bike plate? Order before 2pm for same-day dispatch with free tracked delivery, or bring your V5C and ID to our Hounslow workshop and we’ll make it while you wait.
Order a motorbike plateCollect in HounslowWhatsApp usMotorbike number plate size: FAQs
What size is a motorbike number plate in the UK?
There’s no single legal plate size. The law sets the character size and spacing, and the plate has to be big enough to fit them. For a standard 7-character reg that works out at about 9 x 7 inches (229 x 178mm).
What size are the characters on a motorbike number plate?
On bikes registered from 1 September 2001: 64mm tall, 44mm wide (except 1 and I), a 10mm stroke and 10mm between characters, set on two lines.
Are small motorbike number plates legal?
Only if the characters, spacing and margins still meet the legal sizes. Shrinking the letters or squeezing the spacing to fit a smaller plate makes it illegal.
Do motorbikes need a front number plate?
No. Bikes registered on or after 1 September 2001 must only display a rear plate. Older bikes can show a front plate, but don’t have to.
Can I have a one-line number plate on a motorbike?
No. Motorcycle registrations issued from 1973 onwards must be set out on two lines.
Can I get 3D or 4D motorbike plates?
Raised characters are allowed in law if they’re solid black, in the legal font and size, and the plate meets BS AU 145e. At PlateBoss we make standard printed bike plates only.
What’s the fine for an illegal motorbike number plate?
Up to £1,000, and the bike will fail its MOT.
