Trailer and Caravan Number Plates: The Complete UK Rules

Towing a trailer or caravan comes with its own number plate rule that catches a surprising number of owners out: the plate on the back has to match the towing vehicle’s registration, not have one of its own. Get this wrong and you’re looking at the same fine and legibility risks as any other non-compliant plate. Here’s what the rules actually require.

The core rule: one registration, displayed twice

A trailer or caravan doesn’t have its own separate vehicle registration. Instead, it has to display the same registration mark as the vehicle towing it, on a plate fitted to the rear of the trailer or caravan itself. This applies whenever a trailer or caravan is being towed on a public road — the plate isn’t optional, and it isn’t a general “trailer” plate; it has to show your specific towing vehicle’s actual registration.

This means if you tow with more than one vehicle, or change cars, your trailer or caravan’s plate needs to change too, to always match whatever is currently towing it.

What the plate itself has to meet

A trailer or caravan number plate has to meet exactly the same legal standard as any other UK number plate:

• Manufactured to BS AU 145e, the British Standard introduced in September 2021
• Black characters on a yellow reflective background (rear plates are always yellow, and a trailer/caravan plate is always a rear-position plate)
• Correct Charles Wright font, character size, and spacing
• The supplier’s name, postcode, and BS AU 145e marking displayed on the plate

There’s no reduced standard because it’s a trailer rather than a car — the same compliance rules apply in full.

Why this rule exists

The logic is straightforward: a trailer or caravan isn’t independently identifiable the way a car is, so the system relies on it displaying the registration of whatever’s towing it at the time. This lets it be linked back to a specific vehicle and driver if it’s ever involved in an incident, checked by police, or separated from the towing vehicle unexpectedly. It’s also why the plate has to be updated if you start towing with a different vehicle — an out-of-date registration on the back defeats the purpose of the rule.

What happens if the plate is wrong or missing

Displaying an incorrect, outdated, or missing registration on a towed trailer or caravan carries the same risks as any other non-compliant plate:

• A fine of up to £1,000 for failing to display the correct registration
• Legibility and compliance issues at a roadside check, since a mismatched or non-compliant plate is an immediate red flag to police
• ANPR and camera-reading complications, since automated systems rely on an accurate, legible plate the same way they do for any other vehicle

If you’ve recently changed your towing vehicle, or bought a caravan or trailer secondhand with an old plate still fitted, checking and updating this is worth doing before you’re back on the road towing it.

Do all trailers need a plate?

The requirement applies to trailers and caravans being towed on public roads — if you’re moving a trailer entirely on private land, the same public-road display rules don’t apply in the same way. But the moment it’s on a public road behind a towing vehicle, it needs to display that vehicle’s registration on a compliant plate.

Ordering a matching plate

If you need a new plate for a trailer or caravan — because you’ve changed towing vehicles, the existing plate is damaged, or you’re setting one up for the first time — the process is the same as ordering any other UK number plate: you’ll need proof of entitlement (your V5C, V778, or new keeper supplement) for the towing vehicle whose registration will appear on the plate.

Frequently asked questions

Does a caravan have its own separate number plate?
No. A caravan or trailer displays the same registration as whatever vehicle is currently towing it — it doesn’t have an independent registration of its own.

What happens if I tow with a different car than usual?
The trailer or caravan’s plate needs to show that vehicle’s registration. If it still shows a previous towing vehicle’s plate, it’s no longer compliant.

Is the trailer plate the same colour as a normal rear plate?
Yes. It’s black characters on a yellow reflective background, the standard rear-plate colour, manufactured to the same BS AU 145e standard.

Can I be fined for an incorrect trailer plate?
Yes, up to £1,000 for displaying a non-compliant or incorrect registration, the same as any other UK number plate offence.

Order a matching plate for your trailer or caravan

Get a correctly matched, fully compliant plate through the Car Plates Pro Number Plate Builder. Every plate is BS AU 145e certified and DVLA registered, with prices from £6.99.

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