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Best child car seats

The best child car seats for toddlers and older children

By Anna Studman

Article 1 of 2

Find out which types of car seat are best for toddlers and older children as they grow.

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Child car seats are designed to protect children's soft bones and vulnerable internal organs at each stage of development, from birth to the age of 12, or 135cm, when your child will no longer legally need to use a car seat in the UK.

As a child grows, their skeleton changes, providing better protection for internal organs. Children need different levels of protection as they change from toddlers to pre-schoolers and adolescents.

To find out which child car seats we recommend, visit our child car seats reviews.

Protecting toddlers and pre-school children in child car seats

The best type of child car seat for toddlers is a Group 1 child car seat (suitable from 9-18kg, approximately nine months to four years old), an extended rear-facing car seat or an i-Size seat approved for use up to 105cm, which is also around four years old.

A five-point harness, or impact shield, holds the child in the seat. Both of these are designed to help spread the forces of a crash over a wide area of their chest.

We recommend your child should stay in this type of seat for as long as possible and only move to the next seat when their:

  • weight exceeds the car seat's weight limit (usually around 18kg)
    or
  • height exceeds the car seat's height limit (usually around 105cm)
    or they:
  • grows too tall for the height of the adjustable harness – it should sit 2cm above the shoulder
  • outgrows the head protection – their eyes are level with the top of the headrest, with the head above the protective head rest area of the seat.

Protecting the neck

The risk of spinal cord damage due to momentum of the head in a car crash reduces as your child grows. This means that toddlers can travel in a car seat facing forwards. But research shows that it's safer to keep your child rearward facing for as long as you can.  

Many parents turn their child forwards in a car seat far earlier than they should. When we surveyed 1,552 parents in spring 2017, 52% incorrectly believe it’s safest for children to travel facing forwards in their car seat from nine months old. This is not true.

Group 1 car seats can be used, legally, from 9kg (or around 9-12 months) but this is far too early to turn your baby forward-facing. The latest car seat rules (R129) go some way to address this issue, by making it mandatory to keep babies rearward-facing until they reach 15 months old, at least.

Discover which child car seats scored top in our tests. Browse our car seat Best Buys.

Protecting the chest

By the age of two, the rib cage develops, with the ribs moving downwards to provide more protection for the liver, spleen and kidneys. 

Ribs remain flexible, though, and still need protection from impacts. For this reason, it's best to continue to use a child car seat with a way of spreading forces from a crash across the chest in an accident.

Protecting older children in child car seats

A child's bones continue to strengthen as they grow older read on for more information about the different parts of your child’s body develops:

The skull

The bone-making process is complete by the age of six or seven, but children's skulls remain less rigid than those of adults. 

A good child restraint will limit forward head movement in a front impact, and provide cushioned protection in a side impact. Remember, car seats approved to the old car seat rules (R44.04) don’t have to pass a side-impact crash test..

The chest and rib cage

These remain flexible but become larger and stronger as hard calcified bone gradually replaces soft bone, helping to protect your child’s internal organs.

The pelvis

The pelvis also grows larger, but isn't really strong enough to act as an anchor point for an adult seat belt until around the age of 10.

Keeping older children safe in car crashes

As children grow, it remains important to distribute the crash forces over as wide an area as possible and protect them from contact with the vehicle interior in any type of crash. 

We use a front and side impact for our crash tests as these are two of the most common types of crash.

High-backed booster seats are the best choice when a child has outgrown a Group 1 child car seat with harness or impact shield. These seats raise your child and help guide the adult seat belt across them, so that it lies properly across the chest and pelvis. 

The headrest and side wings, which usually come with added side-impact protection, will help protect your child's head in a crash.

Booster cushion confusion

The rules around booster cushions have changed recently. The older car seat rules (R44.04) have been amended to allow the use of booster cushions for children who are over 125cm in height and 22kg in weight.

We always recommend using a high-backed booster seat wherever possible, for as long as possible, as our experts believe these offer better protection than a booster cushion alone.

Booster cushions raise children up, but most have no way of keeping the shoulder strap of a three-point adult seatbelt in the right place on a child and provide virtually no side-impact protection.

Recently, we’ve tested a handful of multigroup seats which convert to a backless booster seat in Group 3 mode. We don’t usually test booster cushions because their crash test results have been so poor, especially for side-impact crashes, that they were all instantly downgraded to a 0% Don't Buy car seat.

Find out the rest of our child car seat Don't Buys

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