Child car seats: How to fit a child car seat Fitting car seats - getting started

Once you’ve found a child car seat that’s suitable for your child, you’ll need to fit it safely and securely in your car. The process of fitting a child car seat isn’t always as easy as you might think, and there are several dangers to watch out for. 

Choosing the right child car seat and fitting it correctly go hand in hand - your child won't be protected if either is wrong.

Video guide: how to fit a child car seat

To make sure you know how to fit your child car seat correctly, we have created five video guides, from fitting your child's first child car seat to fitting a high-backed booster for older children, to make sure you know how to fit the child car seat you have - simply click on the video you want play below.

Now you have watched the video, make sure you've chosen the correct type of car seat for your child - take a look at our guide to choosing a child car seat if you're not sure.

Examine the child car seat and thoroughly read the instructions before taking it to your car. Always follow the manufacturer’s instructions and keep them with the seat for future reference.

Even a Which? Best Buy child car seat might not fit safely in your car, so have at least one go at installing the child car seat, preferably with the help of an expert, before you buy.

Isofix car seats can be secured without seatbelts

Isofix car seats can be secured without seatbelts to the frame of the car

Isofix car seat fittings

If you have a relatively new car, it's likely to have Isofix mounting points. This is the standard system for all new cars and seat manufacturers, designed to make installing your child safety seat quick and easy. Many parents worry about fitting their car seat correctly, but with Isofix you simply ‘plug in’ a compatible car safety seat to mounting points in the car - rather than fiddling with seat belts.

If your car has Isofix (most made since 2002 do), we strongly recommend you buy a compatible seat and use the mounting system. It’s more secure than the seat belt method, so your child will be better protected in a crash. 

Most cars have two fixing points, but some now have three, where the third (top) tether attaches to a mount behind the rear seat to stop it tipping forward in an accident.

The three-point fixing should work even better than two-point fixing, because it holds the child car seat even more securely. However, the two-point fixing is still generally much better than using seat belts to secure car safety seat. 

If you're buying a new car, make sure it comes with Isofix mountings - sometimes they're a 'no-cost' option.

Trying out the seat 

When you first take the child car seat to your car, check it fits neatly with the shape of the interior. If you're using it in more than one car, check it fits well with each of them.

For some seats, this may require you to remove the car’s head restraint.

Carry child car seats in the back of the car if possible

Carry child car seats in the back of the car if possible

If possible, fit a child car seat in the rear of your car, and never fit one in front of an active air bag. Some cars allow you to disable the airbag – it won’t deploy so it's safe to install a rear-facing child car seat. But always make sure you activate the airbag again before the seat is used for an adult.

For forward-facing seats, some child car seat makers say you should never place forward-facing child car seats on a front seat with an active front airbag; others say it's safe. We're not aware of any evidence to suggest it really is dangerous. 

Our advice is that generally the back seat is safest for children. If you really prefer to have the child in the front, always keep the passenger seat as far back as possible.

Never modify a child car seat in any way.

Buying a seat now? Download and print off our free handy checklist, to help you get the best out of your purchase.

Choosing a child car seat and already a member? You can see full test crash test and ease of use assessment results for over 100 child car seats in our child car seat reviews.

Not a member yet? Sign up to Which? for just £1 and see full Which? test results and crash videos for Britax,  Bebe Confort, Chicco, Concord, Cybex, Jane, Kiddy, Maxi Cosi, and Recaro seats plus many more.

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