How to Find and Verify a Car’s Towing Capacity in the UK

What is a car’s towing capacity?

A car’s towing capacity is the maximum weight it can safely tow. In the UK, this is specified by the manufacturer and shown in kilograms (kg). There are two key figures:

• Braked towing capacity: the maximum weight of a trailer that has its own brakes. This is the relevant figure for caravans, horseboxes, and large trailers.
• Unbraked towing capacity: the maximum weight of a trailer without brakes. This is typically much lower and applies to small utility trailers.

These figures are not optional; exceeding them is illegal and dangerous. The police and DVSA can check your outfit at the roadside. Your insurance may also be invalid if you exceed the limits.

How to find your car’s towing capacity by registration

The quickest way to get the official towing capacity for a specific vehicle is to use a registration number lookup. You can enter your car’s registration plate into an online service that provides UK vehicle specifications. Many of these services show towing capacity, engine size, and other data from the manufacturer.

If you don’t want to use an online tool, you can check the car itself:

1. Look for the vehicle identification plate (often on the driver’s door pillar or under the bonnet).
2. The plate shows four weights: the front axle limit, rear axle limit, gross vehicle weight (GVW), and gross train weight (GTW).
3. The braked towing capacity is usually the GTW minus the GVW, but you must confirm this with the manufacturer’s documentation. The plate does not always give the unbraked limit.

Alternatively, check the owner’s manual or the manufacturer’s website. You will need the exact model and variant, not just the model name, because towing capacities often change between engine types, gearboxes, and trim levels.

Understanding the numbers: braked vs unbraked capacity

Braked towing capacity assumes the trailer has its own braking system. When the trailer brakes are applied, the load on the car’s brakes is reduced, so the limit is higher.

Unbraked towing capacity applies to trailers without brakes. Here the car’s brakes must stop the entire combined weight, so the limit is lower. Most cars have an unbraked limit between 500 kg and 750 kg, but some are lower.

Always check both figures. A small trailer might seem light, but if it is unbraked and your car’s unbraked limit is 500 kg, you cannot legally tow a 600 kg trailer even if the braked limit is 1500 kg.

Also look at the gross train weight (GTW). This is the maximum combined weight of the car, passengers, luggage, and trailer. Even if the trailer is within the towing capacity, you might exceed the GTW if the car is heavily loaded. The vehicle identification plate shows the GTW, but it may not always equal the car’s GVW plus the braked towing capacity. Some cars have a lower GTW to protect the drivetrain.

How to compare different cars’ towing capacities

When comparing cars, use a car towing capacity chart or list. Many motoring websites and forums publish tables showing popular models and their braked and unbraked limits. However, these charts are usually based on the base model or a single variant. Always verify with a reg lookup or the manufacturer’s data for the exact car you are considering.

Here are the key factors to compare:

Don’t just look at the maximum braked figure. Consider what you will actually tow. If you have a 1400 kg caravan, both Car A and Car B above can tow it, but Car A has more margin. The 85% guideline suggests that the loaded caravan should not exceed 85% of the car’s kerbweight for stability, especially for beginners. That would make Car B marginal (85% of 1400 kg = 1190 kg), while Car A is comfortable (85% of 1800 kg = 1530 kg).

Missing information vs genuine drawbacks

When using a car towing capacity chart or a registration lookup, you may find that some data is missing. For example, a chart might show ‘N/A’ for unbraked capacity. That does not necessarily mean the car cannot tow an unbraked trailer; it may simply mean the manufacturer did not certify a figure. In that case, check the owner’s manual or contact the manufacturer. If no figure is available, assume the unbraked limit is low and seek confirmation.

Similarly, a car may have a towing capacity listed as ‘0 kg’ in some databases. This often means that the vehicle is not type-approved for towing in the UK, perhaps because no towbar is approved. Before buying, investigate whether a towbar can be legally fitted. If no towbar type approval exists, that is a genuine drawback for towing, not just missing information.

Another common issue is that manufacturer towing limits can differ between markets. A car sold in the UK may have a lower towing capacity than the same model in another country due to different cooling, suspension, or legal requirements. Always use UK-specific data.

Practical example: shortlisting two cars

Imagine you are choosing between two used cars, both advertised as having a towing capacity of 1800 kg. You plan to tow a 1500 kg caravan. On paper, both work. But when you check the details via reg lookup and the vehicle identification plate, you find:

• Car X: braked 1800 kg, unbraked 750 kg, GTW 4000 kg, kerbweight 1750 kg. The 85% figure is 1487 kg, so the caravan is borderline but acceptable with care.
• Car Y: braked 1800 kg, unbraked 600 kg, GTW 3500 kg, kerbweight 1600 kg. Here the 85% figure is 1360 kg, so the caravan is heavier than recommended. Also, the GTW is lower, so if you load the car with passengers and luggage to its GVW of 2200 kg, the remaining trailer allowance is only 1300 kg (3500 – 2200). You would be over the GTW with a 1500 kg caravan unless you reduce the car’s load.

In this case, Car X is more suitable even though both have the same braked towing capacity. The differences in kerbweight and GTW matter. By gathering these details side by side, you can shortlist based on your personal priorities: stability margin, payload flexibility, or unbraked trailer use.

Steps to verify before buying

1. Note the registration number of the car you are interested in.
2. Use a reliable car towing capacity check by reg service to get the manufacturer’s figures. Confirm the model and variant matches the car (engine, gearbox, trim).
3. Check the vehicle identification plate on the car itself to confirm the GVW and GTW. Calculate the braked towing capacity as GTW minus GVW only if the manufacturer confirms this is valid; some cars have a lower towing limit than this difference.
4. Ask the seller for the owner’s manual or a photo of the towing data page.
5. If you plan to fit a towbar, check whether the car has type approval for a towbar and what the maximum permitted towbar download (noseweight) is. This is separate from towing capacity and is usually 50–100 kg.
6. Compare the figures against your intended trailer’s loaded trailer weight (MTPLM for caravans). Remember that the trailer’s MTPLM must not exceed the car’s braked towing capacity, and ideally the loaded weight should be within the 85% guideline for stability.

Summary

Towing capacity is not a single number. Always check braked and unbraked limits, gross train weight, and kerbweight. Use a registration number lookup for convenience, but verify with the vehicle identification plate and manufacturer data. Compare options based on your actual towing needs and remember that missing information in a database is not the same as a car being unfit for towing – investigate further before making a decision.