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How to buy the right child car seat

Which car seat do you need for your newborn, baby or child?

By Lisa Galliers

Article 1 of 3

Stop car seat confusion with our guide to how much you should spend, whether to go for a group seat or i-size and find out why car seats jargon, such as Isofix, should matter to you

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Car seats are confusing to buy. There's so much jargon to understand, everything from Isofix to i-Size, and booster seats to car seats bases.

In this guide we'll explain everything you need to know to get you started on buying the safest baby or child car seat.

Three of the best baby and child car seats


This Best Buy i-Size car seat is suitable from birth to around 15 months, and it provides a good level of crash protection, getting four stars for overall safety. It’s easy to install and use, plus it has interesting features, including glow-in-the-dark seatbelt guides and a set of stroller adaptors which are compatible with most common pushchair brands.


If you’re looking for a baby car seat to use as part of a travel system, then this Best Buy baby car seat is worth considering. It gets an excellent five stars for safety in our crash tests, and when used on a pushchair this car seat can recline into a lie-flat position that’s better for babies. When used with the Cybex Base Z this seat can also swivel 180-degrees, making it easier to place and remove your child from the seat.


As with its predecessor, this i-Size car seat is a Best Buy. It’s extended rear-facing and gets five stars for overall safety, indicating a very low injury risk in a front or side collision. The seat is spacious and well-padded, and the adjustable Isofix connectors give your child more legroom and they enable the seat to have a secure and stable fit in the car.

Video: How to buy the best baby or child car seat 

Watch our comprehensive video to learn about car seat groups and i-size car seats, when you need to move up to the next child car seat, tips for shopping, fitting more than one car seat in a car and much more.

Which newborn or baby car seat? 

All children need to use a car seat from birth until 12 years old (or until they are 135cm tall, whichever they reach first).

Child car seats are designed to protect children's soft bones and vulnerable internal organs at each stage of development. 

Babies need different levels of protection to toddlers and older children, so when you’re buying your first newborn or baby car seat you need to make sure you're getting one that is suitable specifically for newborns and younger babies.

The car seat you buy needs to meet EU standards.

Your child needs to be in the correct category of seat for his or her age and size.  

All babies start off in a rearward-facing infant car seat. 

Visit our guide to the best baby car seat to find out more about why travelling backwards is a vital part of preventing injuries in a crash. 

You'll need to decide whether you want an infant carrier that can be used a part of a travel system on a pushchair, and you'll also need to consider whether you want a car seat that can be secured to the car by Isofix connectors, the car seatbelt or a base. And see our top 10 baby car seats

Group 0+, i-Size or multigroup seat? 

Click below to help you decide what type of car seat is best for your new arrival. 

You'll find more information on how your car can affect which child car seat is best for you in our guide to factors affecting child car seat fitting.

What are car seat groups?

Child car seats are bought in two ways: either according to your child's car seat weight group or according to the height of your child. So Group 0+ is from 0-13kg – that's from birth to about 12-15 months old. It's possible to buy seats that combine one or more groups, for example group 0+/1, 0-18kg, 40-105cm, or from birth to around four-and-a-half years old. These are known as multi-group or combination seats. 

Find the correct one for you from the different car seat groups.

What is i-Size?

i-Size is part of R129, a new regulation for child car seats that was introduced in 2013. The idea behind i-Size is that all car seats with the i-Size logo will fit in all i-Size approved cars. Your car and your car seat must have Isofix, a fitting system that attaches car seats directly to the frame of your car using connectors. i-Size/R129 seats are based on a child's height (instead of weight). The new seats don't replace the weight-based seats at the moment, they just give you an alternative.

Read more about why an i-Size car seat might be best for you. 

Swivel car seats 

If you're looking for a swivel baby car seat – that's a car seat with a rotating base – you'll be pleased to know there are now more models than ever that have this feature. Some child car seats have a swivel base to help you put your child into the seat, as you can turn it towards the car's door. Other car seats have a swivel base to make it easier to switch between rearward-facing and forward-facing.

Some car seats have a mechanism to stop the car seat being turned forward-facing too early, but others don't. If there is no way to stop the car seat being turned to face forwards too early, it lost marks in our tests because of the potential for misuse. 

Swivel car seatssee which ones we've crash-tested

Isofix car seats 

Isofix is designed to make installing your car seat quick and easy. All new vehicles feature the system. You simply click the Isofix connectors on the base of your seat into the Isofix anchor points in the car.

These anchor points are metal bar connectors built into the chassis of your car. They are often hidden behind the car's seat padding.

Once the Isofix connectors are clicked together, the car seat is secured by a third point – either a support leg that comes built-in into the seat or seat base, or a top tether (a strap that attaches to a mount somewhere behind the rear seat). Both of these work to stop the car seat tipping forward in an accident.

Find out more about Isofix, top tether, support legs and Isofit.

Toddler car seats 

Babies can move up to a forward-facing Group 1 seat when they reach 9kg, but we think this is far too early because their bodies may not be strong enough. It's safer to leave a baby rear-facing until they are at least 13kg or 15 months old.

Many parents turn their child forward-facing too soon, risking more severe neck and brain injuries in a crash. Extended rear-facing car seats, that let you keep your child rear-facing until the age of four/18kg/105cm, are becoming more common.

Car seat-fitting clinics across the country frequently encounter two-year-old or three-year-old children sitting on booster seats or cushions, which are completely inappropriate for such young children, as they offer such little protection in a side crash. Our guide to the best child car seat for toddlers and older children explains the dangers of moving up through the car seat groups too soon.

How much should I spend? 

You can spend as little as £20 on a child car seat, or anywhere up to hundreds of pounds. 

Our advice would be not to scrimp on a car seat: get the best you possibly can.

We crash test each car seat we review, and it's very rare that we see a cheap car seat that provides enough protection to become a Best Buy.

Many parents don't want to pay hundreds for a first-stage car seat, but a £300 extended rear-facing Best Buy car seat, that will last until your baby is four years old, works out around 20p a day over the lifetime of the seat.

Group 2/3 seats can be cheaper and, as your child gets older, they can withstand the force of a crash a bit better, so this is where you can save money but still get a decent high-backed booster seat.

An expensive car seat doesn't always guarantee it's the safest option, though, so check out our best child car seats

Dangers of secondhand car seats 

Second-hand car seats will have wear and tear that could affect the safety protection for your child. The harness, for example, could have been cleaned with harsh chemicals that can make the fabric deteriorate, or the seat could have been involved in a crash and weakened. These are things you cannot tell just by looking at the seat. It's not worth the risk.  

Older seats may not comply with the latest safety regulations, or have gone through updated safety tests, or might be missing the instruction booklet that tells you how to install and adjust the seat safely.

These tips will get you started, but for more advice on what to do before you buy, visit our guide on how to buy the best child car seat.