Car towing guide: braked and unbraked towing weight and capacity

Make your towing experience as simple and stress-free as possible by ensuring you and your car are prepared for caravans and trailers

Simon Ostler
Mar 11, 2022

The ins and outs of towing can be difficult to get your head around, especially if it turns out the car you're currently driving isn't up to the task. If you need to tow something, and you're in the market for a new car that is capable of doing so, it's worth double checking exactly what you're looking for to make sure the car you end up with is fit for purpose.

If you're one of the many thousands of drivers who like to head off during the summer to embrace the delights of a caravan holiday, the car you drive is going to be an important factor in how successful your plans are going to be.

Remember that you can’t travel as fast when towing a caravan or trailer. You must stick to 50mph on a 60mph single-carriageway road, and not exceed 60mph on a dual carriageway or motorway. This is because your braking distance will be longer, and because the trailer will be hard to control if it starts swaying at high speeds.

Experienced caravanners will no doubt have got their holiday routine nailed down by now, but if you're new to the process of towing a caravan across the Great British countryside then you might well be wondering how best to go about it. While we won't be able to help you decide which caravan to buy, we can give you plenty of advice on which car is likely to be best to tow it with.

Or, if you can't stand the idea of going away in a caravan, but you do need a car that can manage to tow your heavy trailer, we can help you crunch the numbers to find your perfect tow car.

Read on for more details on towing with your car, how much it can tow, and what to look out for when shopping for an ideal tow car.

Car towing capacity

A car's towing capacity is split into two sections: unbraked and braked. In most cases, a car manufacturer will quote maximum towing capacity figures for every car it builds. The towing capacity is measured in kilograms (kg), and these figures relate to the amount of weight the car can tow safely, but this is also a legal limit, too, so you should never exceed this capacity.

If you can’t find a towing figure for your car, it’s likely that it hasn’t been approved for towing. Many electric cars can’t tow, for example, because the extra weight would overwhelm the car’s brakes and motors. However, there is a growing number of electric tow cars to choose from. Meanwhile, if you have centrally mounted exhausts, you won’t be able to pull a trailer as there’s nowhere to mount a towbar.

Unbraked towing capacity

The unbraked towing capacity will almost always be the lowest of the two figures, and this is because it refers to towing something that is not fitted with its own brakes - usually a small trailer. Therefore, the only means of slowing down the car and the trailer are the car's brakes, and because of the additional weight attached to the car, this needs to be very carefully regulated to ensure your car is able to stop within a safe distance. 

As a driver, it's always important to bear in mind this reduced braking efficiency when towing an unbraked trailer, and therefore you should always adjust your driving accordingly - reducing your speed, and allowing for a much longer braking distance in traffic and at junctions.

The legal maximum weight limit for an unbraked trailer is 750kg, but smaller cars may be limited to a lower weight - this should be quoted by the manufacturer and usually found in the vehicle's handbook.

Braked towing capacity

A car's braked towing capacity is usually a much higher figure, and refers to towing something that is fitted with its own brakes. This means the trailer or caravan will apply its own brakes whenever you push the brake pedal in your car, aiding with deceleration and making it possible to tow much larger and heavier objects.

Much like in the case of unbraked towing capacities, the quoted limit for braked towing capacity is set for both safety and legality, so exceeding this limit should be avoided.

The most common advice for all but the most experienced tow car drivers is to ensure the weight of what’s being pulled is no more than 85% of the car’s kerb weight - this is another figure that should be quoted by the manufacturer and essentially refers to how much your car weighs when you're driving it.

Additional considerations for towing

Another figure to be aware of is the tow ball weight, or nose weight. This is the force of the caravan or trailer pushing down on your car's tow bar, and there will be a maximum permitted sum given by the car maker. Again, it varies by each manufacturer, but it’s normally around 75kg. It can be measured with a special gauge that is likely to be a useful tool if you're concerned whatever you're planning to tow might be too heavy for your car.

And finally, cars are also subject to what’s called maximum authorised mass (MAM). This is the maximum the car can weigh when people, luggage, roof boxes and any trailers are taken into account. You should check the weight of any trailer or caravan with its manufacturer, and ensure that you're able to keep the overall weight below the MAM, as again this could cause safety concerns if your car's brakes are unable to manage excessive weight.

Small unbraked trailers should be compatible with most cars. For example, the Volkswagen Polo, a relatively small hatchback, is capable of towing an unbraked trailer that weighs 500kg, which ought to be more than sufficient for a trailer load of garden or DIY waste.

Can I tow a caravan?

The answer to this question is, most likely, yes. However there are a couple of details it's worth keeping an eye on.

First of all, you need to make sure the car you're driving is capable of towing the weight of a caravan. If you're driving a car with a 1,100kg braked towing capacity and your caravan weighs 1,300kg, then you're going to need to change one of these factors.

If however, your car is ready and raring to kick-start your summer holiday, you just need to ensure that you as the driver are also covered legally to complete the journey. These are the criteria for towing that you'll need to be aware of.

  • If you passed your driving test before 1 January 1997, you’re generally OK to drive a car and caravan combination of up to 8,250kg, and this can be confirmed by checking your driving licence on the website.
  • If you passed your driving test after 1 January 1997, you're generally OK to drive a car and caravan combination of up to 3,500kg. If you want to tow something heavier than this, then you can take the DVLA's towing and trailer test.

Do you need insurance for towing?

Yes, and you may need additional cover. Check your car insurance policy or speak with your insurer to check whether you are covered for towing. If you aren’t, there may be an additional insurance premium to pay.

Towing a car behind a caravan

An alternative to towing a caravan with a car is towing a car behind a motorhome. This may appeal if you only need a small car the rest of the time, while the advantage when you get to your destination is that you still have a car to explore the local area while the motorhome is parked up on-site. There are still a number of things to consider, but our guide to towing with an A-frame will guide you through it in detail.


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