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Baby & child.

22 June 2021

Baby or child car seats shopping checklist

Buy a child car seat with confidence. Go armed with our top tips on what to look for and how to get the right advice in store.
Alison Potter
Baby being strapped into car seat

Whether you're buying your child car seat from Halfords, John Lewis or an independent retailer, watch our video above and read our checklist below to make sure you get the right car seat.

Our car seat reviews reveal the seats that passed Which? crash tests.

Video: How to buy the best child car seat

Shopping checklist: questions to ask

Download our checklist to make sure next time you visit a store you're getting asked the right questions.

There is a file available for download. (109 KB). This file is available for download at .

What is your child's age, weight and height?

Measure your child

Make a note of your child's weight and height, as this will determine what seat you’ll need to buy. Any good shop will ask for this information.

Record the weight in imperial and metric units – people often use pounds and ounces, but car seats are approved for weight groups in kilograms. Noting down your child's weight in both units will prevent mistakes when converting from one to another. Measure their height in centimetres.

Check they are the right age for the car seat

Although you'll primarily be using weight and height to choose the right car seat for your child, don't discount their age. Tell the retailer how old your child is when considering whether a particular seat is right.

52% of parents in our 2021 survey* thought it was true that you need to change your baby car seat to a Group 1 car seat on the child's first birthday. 

Many car seat experts feel this is too young to turn a baby forward facing, so don't move a size up too early on account of age. 

All i-Size (R129) baby car seats help to address this issue, as it's mandatory to keep your baby rear facing until 15 months in an i-Size baby car seat. 

Find out more in our guides to i-Size car seats and car seat weight groups.

*In February 2021, Which? surveyed 2,021 parents with children under the age of five years.

Check your child in their current car seat

If you’re changing from one seat group to the next, weight isn’t the only factor. Check the position of your child's head in relation to the top of the seat.

You should change from a rear-facing Group 0+ seat when the crown of your child's head is level with the top of the seat. A child’s delicate head is exposed to more severe injuries in a crash if it pokes up above the top of the seat.

Some baby car seats now have the option to keep your baby rear facing until they are 18kg, 105cm tall or around four years of age.

For Group 1 forward-facing seats you'll need to change up when your child's eye level is in line with the top of the seat, otherwise there will be less protection in a crash. 

Mum shopping for car seat

Is your car compatible?

Not all car seats fit in every car. Look in your car’s manual or check with the manufacturer to see which child car seats are approved for use in your make and model of car, and don’t forget to also check for any other car you're likely to use the seat in.

Before you set your heart on a particular car seat, there are a few bits of key information about your car you’ll need to find out:

Isofix points top tether and underfloor storage

Does your car have Isofix?

If you have a relatively new car, it’s likely to have Isofix mounting points (most cars made since 2002 do). These are two anchor points hidden in the padding on the back seats of the car. Some are easier to spot than others. 

Isofix is the standard system for all new cars and car seat manufacturers, and is designed to make installing your child safety seat quick and easy. 

If your car has Isofix, we strongly recommend you consider a compatible seat and use the mounting system. It’s usually easier to secure the seat with Isofix than by using the seatbelt, so you should have a higher chance of fitting it correctly.

It's important to check the manufacturer fit list to make sure an Isofix child car seat will fit your make and model of car. Some Isofix car seats will only fit in certain seating positions within a vehicle.  

Read our guide to Isofix car seats to find out more.

Does your car have underfloor storage compartments in the rear?

Car seats that use a support leg, or ones that can be fixed on to a base that uses a support leg, can’t always be used in cars that have underfloor storage compartments in the back.

This is because the underfloor storage cover isn’t strong enough to withstand the forces of a crash, and the support leg could break through the cover – which would seriously affect the structural integrity and the positioning of the car seat. 

If you do have underfloor storage, and your car manufacturer recommends you don’t use a seat with a support leg, then your car should have a top tether mount instead. 

Does your car have top tether mounts?

Since November 2012 all new cars should have a top tether mounting point. This is a third anchor point for fixing a car seat to stop it tipping forward in an accident, if you can’t use a car seat or base with a support leg.

Does your car have front passenger airbags?

Don't put a rear-facing baby car seat (infant carrier, Group 0+) on the front passenger seat when the airbag is activated. Your child could be seriously injured by the force of the airbag going off during a crash.

You can use the front seat with a baby car seat if you can deactivate your front passenger airbag – check your car’s instruction manual to see whether this is possible. Check with your insurer whether deactivating the airbag affects the level of your insurance cover, too.

Mum looking at car seats with baby

Is this car seat suitable for your lifestyle?

Finding the right child car seat to transport one child in a single car is relatively easy – but finding one that will fit in with the whole family’s lifestyle is more of a challenge.

Read our top tips on things to think about before buying your car seat – it will help you to choose and fit the right seat for your family’s needs.

Will the car seat be used in other cars?

You need to know whether the cars you most commonly use have Isofix mounts, or whether you'll need a seat that you can fit using the seatbelt. Think about the cars used by grandparents and childminders, if they will use your seat. Not all car seats fit in all cars.

How many children do you transport?

Fitting two or more child car seats in a car can be difficult, so make sure you think about the other children you transport regularly.

How tall are the parents?

If you have a tall passenger in the front seat, it can affect how much space there is for a rear-facing child car seat, and also the positioning of the foot rest. This could influence which seat you use for your child when the whole family is travelling.

Make a shortlist

Having some idea of what you want in advance helps you to compare car seats and make the right decision. Buying from a retailer with a fitting service is ideal because they will make sure your chosen car seat fits in your car before you buy.

See our best child car seats that offer your child the best protection and are easy to install.

Going to a retailer with a fitting service

If you're shopping from a retailer with a fitting service, phone up and make an appointment with a trained car seat fitter who can help with choosing a suitable seat and showing you how to fit it properly.

Once you’ve established that the seats you’re interested in are suitable for your car, ask the assistant for a demonstration on their in-store rig. This will allow you to see how to fit and adjust the seat, without the complexities of being in the confined space of a car.

Have a go at strapping your child into the seat, and make sure you can adjust everything that’s likely to need adjusting during the time your child will be using it.

Adjustments are likely to include:

  • tightening the harness
  • reclining the seat to allow kids to sleep more comfortably
  • changing from rearward to forward facing (if applicable)
  • adjusting the height of the harness
  • removing and reattaching padding and inserts for infants
  • removing harnesses completely (multi-group seats)
  • adjusting headrests and any side padding.

Once you’re happy that the seat seems right for your child, ask for a demonstration in your car, so you can see that it actually fits. Trying a child seat in your own car is absolutely essential.

Sometimes, the angle of the car’s back seat or the position of its seatbelt mountings and buckles can get in the way of a good seat, making it useless.

Strap in your child and have a go at making all the adjustments. Make sure you’re happy with the fit of the seat in the car, and of your child in the seat.

Again, this is your chance to ask the retailer questions before you're on your own at home with the seat and a confusing set of instructions.

Only when you’re satisfied that the seat works for you, your child and your car, are you ready to buy.

How to get a free car seat fitting check

Some local councils hold regular car seat fitting clinics, where you can get the fitting of your seat checked by trained fitters. Look on your local council's website, or check local press for details of car seat fit clinics. 

Other organisations, such as Child Seat Safety and Good Egg Safety, also run free car seat check days around the UK.