Trailer Number Plate Rules: What the Law Says (UK and Abroad)
Trailer number plate rules, the short answer: in the UK, a trailer or caravan must carry a number plate showing the registration of the car that’s towing it, fixed to the back of the trailer. It’s a normal yellow rear plate, made to the same rules as the one on your car. Separately, if you tow a trailer over 750kg into most European countries, it needs its own DVLA trailer registration number and a white trailer plate as well.
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 INF291, DVLA leaflet INF104 and the Road Vehicles (Display of Registration Marks) Regulations 2001, October 2026. How we write our guides.
In this guide
- Towing in the UK: the same reg as your car
- Towing abroad: trailer registration numbers
- What you need to get trailer plates made
- What we make most
- FAQs
Towing in the UK: the same reg as your car
The law puts it simply. A rear registration plate has to be fixed on the back of the vehicle, or, when the vehicle is towing a trailer, on the trailer. Your car’s rear plate is hidden once the trailer is hitched up, so the trailer has to show the same registration instead.
That plate follows all the normal rear plate rules:
- black characters on a reflective yellow background;
- the standard font, character sizes and spacing;
- the supplier’s name and the BS AU 145e mark.
If you tow with more than one car, you need a plate for each, and you have to swap it to match whichever car is towing.
Need a plate for your trailer or caravan? Our same-reg trailer plates are made to the same standard as your car’s rear plate, from £19.99.
Order a trailer plateSend us a photo on WhatsAppTowing abroad: trailer registration numbers
The DVLA’s trailer registration scheme is for towing abroad. Its leaflet INF291 says you must register all trailers over 750kg to drive them in most countries in Europe, apart from Ireland, Cyprus, Malta and Spain. That covers commercial trailers and non-commercial ones like caravans.
A registered trailer gets its own trailer registration number (TRN):
- Format: one letter followed by seven numbers, set out over two lines. DVLA numbers never start with C.
- Plate: the same shape as a standard motorcycle plate, with solid black characters on a white background. Characters are 64mm tall and 44mm wide (except 1 and I), with a 10mm stroke and 10mm between characters.
- Position: on the rear of the trailer, visible and vertical. If that isn’t possible, on both sides.
- Abroad, it goes alongside your car’s registration plate, not instead of it.
What you need to get trailer plates made
| Plate | What to bring or send |
|---|---|
| Same reg as your car (UK towing) | The same as for any car plate: photo ID and the towing vehicle’s V5C or other proof of entitlement. See our documents guide. |
| Trailer registration number (TRN) | Your trailer registration certificate, or the trailer number plate authorisation certificate (valid for 5 days), plus ID proving your name and address. |
The rules can change, so check the latest DVLA guidance (linked below) before you travel.
What we make most
Most of the trailer plates we make are the commercial ones with a DVLA trailer registration number. We make the same-reg plates for UK towing too, and both are made to the same standard as our car plates.
Both can have a UK badge with the Union flag, the same as a car plate.
Trailer plates and fixings
Trailer plates made to DVLA rules. Order before 2pm for same-day dispatch with free tracked delivery, or collect from our Hounslow workshop.
Shop number platesCollect in HounslowWhatsApp usTrailer number plate rules: FAQs
What number plate does a trailer need in the UK?
A rear plate showing the registration of the vehicle towing it, made to the same rules as a car’s rear plate: yellow, reflective, standard font and BS AU 145e marked.
Do trailers need their own registration?
Not for UK-only towing. Trailers over 750kg must be registered with the DVLA to tow them in most European countries, apart from Ireland, Cyprus, Malta and Spain.
What does a trailer registration number look like?
One letter followed by seven numbers, set out over two lines on a white plate the shape of a motorcycle plate.
Can I use the same trailer plate with a different car?
No. The trailer must show the registration of the car towing it, so you need a plate that matches whichever car is towing.
What documents do I need for a trailer registration plate?
Your trailer registration certificate or trailer number plate authorisation certificate, plus ID proving your name and address.
Does a caravan need a number plate?
Yes. When towed, a caravan must display a rear plate with the towing vehicle’s registration.
Can trailer plates have a UK flag badge?
Yes. We can make trailer plates with a UK badge and Union flag, the same as car plates.
