Child seat weight groups

Child seat groups under Regulation 44

Child restraints approved to Regulation 44 will cover one or more groups based on your child's weight

Regulation 44 defines performance requirements for child safety seats in weight groups from 0 and 0+ for newborn babies, up to group 3 for children weighing 22-36kg.

  • Group 0, 0+ – Infant carriers for babies from birth to 13kg (0+) or 10kg (0) (approx. 15 months or 6-9 months)
  • Group 1 – For children from 9kg to 18kg (around 9 months to 4 years)
  • Group 2 – Booster seats for children from 15kg upwards (from approx. 4 years)
  • Group 3 – Booster cushions for children 22kg (approx. 6 years up) and upwards and more than 125cm tall 

Car seats

Baby seats (group 0+ and 0)

Infant carriers for babies from birth to 13kg (0+) or 10kg (0) (approx. 15 months or 6-9 months)

Your newborn baby won't be able to support his or her head until about six weeks, and won't be able sit up until much later. This is why child seats for the youngest children are all rear-facing, and designed to support the head, neck and back evenly.

  • The smaller 'Group 0' seats can only be used for children up to 10kg, a weight most babies will reach by around 6-9 months.
  • Group 0+ seats are a better choice because they are suitable for children up to 13kg (around 15 months) and allow you to keep your child in a safer, rear-facing seat for longer.
  • Seats fitted using the adult belts are easily moved from one car to another – assuming the adult belts are long enough.
  • Infant carriers fitted using the ISOFIX system typically combine a 'base', attached to the car, and a seat that clips easily into and out of the base. A support leg on the base prevents forward rotation in an accident. Check your handbook to make sure you buy the right ISOFIX category and 'size class'.
  • If price is a concern, ask your local authority Road Safety Officer about hire schemes in your area.
'Two-way' seats

Seats that can be used rear-facing for the first 9 months and then forward-facing up to the age of three or four years may look a good idea if money is tight, but they are a compromise:

  • They’re bigger and heavier than an infant carrier so are less convenient.
  • Instructions can be complicated –  two-way seats are often installed incorrectly.


Child car seats (group 1)

In-car safety for children from 9kg to 18kg (around 9 months to 4 years)

Rear facing provides better protection and lower risk of injury in a crash, so even though seats in this group may technically be approved for children from 9kg – which could be as young as six months old – it's best not to rush to get your child into a forward-facing seat.

  • Seats in group 1 usually consist of a seat shell attached to a frame. Your child’s held by an integral five-point harness and the frame’s attached to the car using the adult seat belts or ISOFIX anchorages.
  • Some booster seats, aimed at older children in groups 2 and 3 are supplied with a removable harness for younger children, so it’s possible to buy a single seat for your child covering the range from 9 months or so up to their 12th birthday. Look for seats marked 'Group 1,2 and 3'.
Rear-facing seats
  • Rear-facing seats can be up to five times safer, and children in Sweden travel rear facing until the age of 4 or 5 years using group 1 seats approved to 25kg.
  • Rear-facing group 1 seats made for the Swedish market and approved for children up to 18kg or 25kg are available in the UK, but you’ll have to hunt for them.

It's important to try before you buy to make sure a new child seat is compatible with your car, but this is even more important if you’re thinking about buying one of these bigger rear-facing seats.

You mustn’t use any rear-facing child seat on a passenger seat where an active passenger airbag is fitted.

Fitting tips for group 1 seats:

Fitting the adult belt correctly around the frame and adjusting it so the seat is tight in the car takes time and effort.

  • Compared to booster seats, this type of seat can be harder to move from one car to another.
  • Few, if any, 'universal' child seats can actually be fitted properly in every seating position in every car.
  • Check the maker’s application list and ask the shop to show you how the seat can be installed correctly in your car.
  • Fitting mistakes are common – read the fitting instructions carefully and keep them with the seat.
  • Make sure it’s tight – kneel into the child seat to compress the car seat cushion underneath while pulling the adult seat belt as tight as possible.
  • Check the seat before every journey and re-tighten it if necessary.
  • The harness should be comfortably tight and without twists which could increase injury. Place your hand flat on the child's chest and pull the harness up tight against it for the ideal adjustment.


Booster seats (groups 2/3)

Car safety seats for children from 15kg upwards (from approx. 4 years)

  • Booster seats are popular with parents because they're light and easy to fit.
  • They're popular with children too, which is important because a happy child is less likely to be a distraction.
  • The latest booster seats have features designed to give side impact protection – this is important as one in four crashes involves side impact.
  • Adjustable high-back booster seats with deep side wings that can be adjusted up and down will give side-impact protection until your child reaches 12 years or 135cm.
  • Some booster seats include a removable, integral five-point harness so that they can be used for the younger weight group (Group 1) too. Look for seats marked Groups 1, 2, and 3.
Fitting tips for booster seats:
  • The diagonal part of the belt should lie across your child's shoulder rather than neck.
  • The lap part of the belt should lie across the top of your child's thighs, not around the abdomen.
  • Belts should lie flat. Avoid twists, which can increase injuries in a crash.
  • Never pass the diagonal part of the belt under your child's arm.

Booster seats suffer less from car compatibility problems compared with group 1 seats. They're easier to fit and more likely to be fitted correctly.


Booster cushions (group 3)

Minimal safety but light and convenient for children 22kg and upwards (approx. 6 years up)

Most booster seats are approved for groups 2 and 3 and can be adjusted to give effective side and frontal impact protection for children all the way from around 4 years up to 12 years or 135cm tall.

But there may be occasions when it's not convenient to use a 'high back booster' and this is where the simple booster cushion comes into its own.

  • If your child's often picked up from school by other parents it may be better to send them with a small and light booster cushion, easily carried under the arm.
  • Being small, easy to carry, and cheap, booster cushions are ideal as a spare for occasional journeys with friends or relatives where it's not practicable to transfer the child's main seat.
  • A booster cushion is a good alternative to the adult belt alone as it will improve the fit of the diagonal belt on your child's shoulder and help make sure that the lap belt lies properly across the top of your child's thighs.
Fitting tips for booster cushions
  • Your child's restrained using adult belts that also hold the booster cushion in place by passing around moulded 'ears' at its rear.
  • Make sure that the diagonal belt passes across your child's shoulder rather than neck, and that the lap belt passes across the top of your child's thighs.
  • Some booster cushions have a strap and clip to improve the fit of the belt by lowering the over-shoulder height of the diagonal part of the seat belt.
  • Booster cushions mustn't be used in seats where there's only an adult lap-belt. (Some group 1 child seats can be installed using a lap belt alone).
New booster cushion regulations

A booster cushion doesn't provide anything like the protection offered by a high-back booster, particularly for younger children.

Reflecting this, new booster cushions launched after March 2017 will only be approved for children over 22kg (around 6 years) and more than 125cm tall. This will be clearly marked on the label.

Current booster cushions, approved for children weighing 15kg and over (around 4 years), can remain on sale and you can continue using them. This is a change to regulations affecting the approval for sale of new products rather than a change to the law on using child seats.

  • Your child must use a child restraint appropriate to their age/weight.
  • A booster cushion may be 'appropriate' for children over 15kg or children over 22kg and 125cm depending on when they were developed and approved for sale.

Any child seat/booster is better than none, however, even for the older child, a high back booster does provide more protection.

9 February 2017 

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