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Child car seat safety

Baby and child car seat safety features

By Alison Potter

Article 1 of 4

Get to grips with the common features of each type of child car seat (from baby onwards), and how these work to protect your child.

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Child car seats are split into groups according to the weight or the height of the child they're intended to protect. The seats in each group are designed to protect your vulnerable child from crash injuries as he or she grows from a baby to a teenager.

Once you know which sort of child car seat you're looking for, head over to our child car seats reviews to see the best – and worst – performers in our rigorous tests.

Group 0 and 0+ - infant carriers and baby car seats

Group 0 seats (for babies up to 10kg) aren't as common as they used to be, and tend to be lie-flat carrycot car seats, which can be useful for premature babies and babies with medical conditions, or if you prefer to have your newborn travel in a lie-flat position. More popular, are the rear-facing Group 0+ seats, which are suitable for babies up to 13kg (roughly 12-15 months). 

Key features

  • Rear facing to support and protect your infant's head, neck and spine.
  • Protective shell, head support and padding.
  • Secured to the car via a base (Isofix or belted) or the adult three-point seat belt.
  • Three- or five-point harness to restrain your baby; some have a one-pull harness tightener.
  • Semi-supine position (45-degree recline angle to provide good support for your baby's head and neck).
  • Handle to make it easier to put the seat in your car with your baby inside.
  • Shaped bottom so it can be used as a rocking seat.
  • Some models can fit on a pushchair chassis (with or without adaptors) to be used as part of a travel system.

Travel systems and child car seats

Some Group 0 and Group 0+ child car seats are designed to be removed from your car and placed on the frame of a pushchair to be used as a travel system, letting you easily transfer your baby between car, pushchair and home, which is great if you spend a lot of time on the move. 

Some travel system pushchairs are sold with a Group 0+ car seat as a package. This may seem like a great way to save some cash, but we'd always advise you to buy the best car seat you possibly can, rather than settle for one included in a bundle. If you do want to get a travel system package, check if the car seat included with your pushchair is a Best Buy car seat, or not.

Although some infant carriers are designed to be used on a pushchair, babies – particularly premature or newborn ones – should not be left in their car seats for long periods. The slightly scrunched up position they sit in can affect their breathing in as little as 45 minutes.

Browse the 10 best travel systems that scored most highly in our reviews. 

Group 1 - toddler seats

Group 1 seats are usually forward facing, although extended rear-facing (ERF) Group 1 seats are becoming much more common in the UK.

Key features

  • Protective shell and padding.
  • Secured to the car via a base or the seat belt.
  • Five-point harness or impact shield to restrain your toddler.
  • Adjustable head support.
  • Removable seat liners and adjustable harness position to provide more space for your growing child.
  • It's possible to recline some seats to give a more comfortable sleeping position.

Discover the pros and cons of rear facing child car seats

Groups 2/3 - high-backed and booster seats

Group 2/3 seats are designed to raise children up from the car's existing seat so that the adult three-point seat belt is positioned correctly across their pelvis, chest and collarbone.

Key features

  • You use the three-point adult belt to restrain your child.
  • You use belt guides to position the adult seat belt on your child.
  • Adjustable headrests move upwards as your child grows.
  • Some seats have attachments to the car's Isofix mounts to keep the seat secured in the car when it's not belted in.
  • Some seats also offer adjustable side-impact protection, reclined positions and drink holders.

Some high-backed booster seats have backs that can be removed as your child grows bigger, allowing you to just used the booster cushion as a child car seat. You can also buy cheap booster cushions that do not have a high-back (group 3 seat).

We strongly recommend that you don't remove the back of high-backed booster seats or use a backless booster cushion.

Doing this removes the protection, leaving children vulnerable to head and side injuries, particularly in side impact crashes, which make up a significant proportion of all car accidents.

It also makes it more difficult to position the diagonal strap of a three-point adult seat belt correctly across the shoulder.

Backless booster seats - watch a crash video to see why we don't recommend them