Child car seats, restraints and seat belts

Children are much more vulnerable than adults in a car so taking time to make sure you use the right child seat (restraint) or booster correctly, could save your child's life. Drivers and passengers are more likely to be killed or seriously injured when they don’t wear a seat belt.

Child car seats, restraints and the law

The law states that you must use the right car seat for your child in cars, mini buses, vans and other goods vehicles. 

It is the driver’s responsibility to make sure that any child under 14 years of age uses a seat belt or the right child restraint. Any child restraint used must conform to EU safety standards that is either Regulation 44.04 or Regulation 129 (also known as i-Size seats).

All children up to 135cm (approximately 4ft 5in) in height, or up to 12 years of age (whichever occurs first), must use a suitable child restraint – that is, one that is suitable for your child’s height or weight.

There is a fixed penalty fine of £60 and three penalty points for not using the right child restraint.  If the case goes to court this could increase to a maximum fine of £500 for any occupant anywhere in the car.

Birth to three years of age

Children under three years of age must use a suitable child restraint.  There is only one exception: 

  • a child under three may travel unrestrained in the rear of a taxi or a minibus if the right child restraint is not available 

​Rear-facing baby seats must not be used in a seat protected by a front air-bag unless the air-bag has been deactivated. 

From three to 12 years old

In vehicles where seat belts are fitted, children from three years to 12 years and up to 135cm in height (about 4ft 5in) must use the right child restraint. 

Three exceptions allow these children to travel in the rear of the vehicle with the use of an adult seat belt:

  •  in a taxi if the right child restraint is not available
  •  for a short distance, in an unexpected necessity - if the right child restraint is not available
  •  where two occupied child restraints in the rear prevent the fitting of a third child seat and no suitable child restraint is available for use in the front passenger seat

There is also an exception for children with a a medical certificate saying that it is not advisable on medical grounds to wear a seat belt.

A child  taller than 135cm must wear a seat belt where one is fitted.

Children 12 to 13 years or over 135cm in height

Children aged 12 or 13 years or over 135cm (regardless of age) in height must wear a seat belt where one is fitted.  

Summary of seat belt and child restraint requirements

Driver or passengers Front seat Rear seat Who is responsible?
Driver Seat belt must be worn if fitted   Driver

Child under three years of age

The right child restraint must be used The right child restraint must be used. If one is not available in a taxi or minibus, the child may travel unrestrained Driver
Child from third birthday up to 135cm in height (or 12th birthday which­ever they reach first) The right child restraint must be used

The right child restraint must be used where seat belts fitted.

Must use adult seat belt if the right  child restraint not available:

in a taxi or minibus;

for a short distance in an unexpected necessity;

if two occupied child restraints prevent fitting a third and suitable child restraint is not available in the front passenger seat.

Child 12 or 13, or over 135cm in height Seat belt  must be worn if fitted  Seat belt must be worn if fitted Driver
All passengers 14 and over Seat belt  must be worn if fitted  Seat belt  must be worn if fitted  Passenger

Choose the right child car seat for your child

You should choose a child car seat or restraint based on your child’s height or weight.

There are currently two European standards for child restraint systems.  These are known as Regulation 44 and Regulation 129 (or i-Size).  Seats manufactured to either standard will have a label showing a capital ‘E’ in a circle - as shown in the picture. ECE R44 and ECE R129 conformance labels should show the weight and/or height category for the product, the country of approval ("E11" for example, means England) and the unique approval number

The label will indicate which standard the child car seat meets – Regulation 44 or Regulation 129 (i-Size).  Regulation 44 child car seats are based on weight with an age recommendation.  Regulation 129 (or i-Size) child car seats are based on height/ length and have a maximum weight. The label will tell you the weight or maximum height/ length the child car seat is designed for.

i-Size symbol on child car seats for cars fitted with ISOFIX anchorage points If you choose a Regulation 129 (i-Size) child car seat you will need to check that your car is fitted with ISOFIX anchorage points.  These child car seats are marked with the i-Size symbol which is shown in the picture on the right.  If you are not sure, check with the manufacturer. 

Regulation 44 seats will be phased out over time and replaced with Regulation 129 seats.  Until then, seats manufactured to either standard are safe and perfectly legal so long as they are used properly. 

Regardless of which standard of child car seat you choose, check the label to make sure that it is suitable for your child and only use it in keeping with the manufacturer’s instructions.

When buying a child restraint, if possible, try it in your car before you buy.  Not all seats will fit or be suitable for your car.  If you plan to use your child car seat in more than one car it is important to check that it fits other cars as well.  Speak to the shop sales adviser who will give you advice and may show you how to fit the restraint correctly.

ROSPA website has  further information and practical tips on choosing and using child car seats.

Types of child restraints

A child restraint is the collective term for rear facing baby seats, forward facing child seats, booster seats and booster cushions.

Manufacturers may use different names and some products may cover more than one weight or height so it is important to read the label.

Regulation 44 child car seats

Regulation 44 child car seats are based on weight with an age recommendation and are divided into five weight groups:

Group Weight Age range (roughly only)

Group 0

up to 10kg (22lbs) Birth to six to nine months
Group 0+ up to 13kg (29lbs) Birth to 12 to 15 months
Group 1 9 to 18kg   (20 to 40lbs) 9 months to 4 years
Group 2 15 to 25kg (33lbs to 55lbs) From about 4 years to 6 years
Group 3 22 to 36kg (48lbs to 79lbs) From about 6 years

Regulation 129 child car seats 

Regulation 129 child car seats are based on length / height, have a minimum weight and are also known as i-Size seats. Child car seats approved according to Regulation 129 will be phased in over time.  In the first phase (which is already in place) manufacturers are producing child car seats suitable for children up to 105cms – around four to four and a half years of age:  

  • the first stage i-Size child car seat is designed for children from birth up to 15 months and must be rear-facing - this will accommodate a child with a length/height up to about 83cm
  • in addition to the size range (length/ height) a maximum weight - up to which the child car seat can be used - is shown - so it is also important that you know the weight of your child
  • each child restraint manufacturer will specify the length/ height range and maximum child weight for their product
  • it is possible to keep your child in a rear facing seat beyond 15 months to 105cm length/ height - forward facing child car seats can be used from 15 months but you should delay this as outlined below under 'Use the restraint correctly'
  • it is important to check the label to make sure the child car seat is suitable for the length/ height of the child using it and that you observe the maximum weight allowed 

Use the restraint correctly

Every year too many children are killed or seriously injured on the roads – often because they are not properly restrained when travelling in a car. So make sure you understand the law and give your child the best possible protection.

Many seat experts believe that it's better and safer to keep your child in the lowest group seat for as long as possible. This means staying in their current stage seat until the maximum weight or height limit is reached.  Because children grow and develop at different rates it is important to keep a watch on your child’s height and weight to make sure that they don’t move up a stage too early or too late. 

You must only use a child restraint if your car’s seat belt has a diagonal strap, unless the child restraint is either: 

  • specifically designed for use with a lap seat belt only or  
  • fitted using ISOFIX anchor points 


  • check the label to make sure the child car seat is suitable for your child’s weight and height
  • fit the child restraint properly - follow the manufacturer's instructions
  • every trip - allow time to get the child comfortably strapped in
  • where using an adult belt to secure the restraint - make sure it passes through all the right slots
  • make sure that the child restraint is tight in the adult seat
  • make certain that the adult seat belt buckle is not bent over or resting on the child restraint frame
  • never fit a rear-facing restraint with an active airbag in front of it
  • check the vehicle handbook and follow the advice about children and airbags - where fitted
  • deactivate any front airbags before fitting a rear-facing (baby) restraint in a front seat
  • never modify the restraint or adult seat belt to make it fit
  • never fit a child restraint in side-facing seats

New booster seat rules - no change for existing seats

  • new rules are now in force for backless booster seats (booster cushions) 
  • ​the new rules apply to both Regulation 44 and Regulation 129 i-Size backless booster seats 
  • this means that manufacturers are not allowed to introduce new models of backless booster seats (booster cushions) for children shorter than 125cm, or weighing less than 22kg 
  • this change to technical standards means that the range of products available on the market will be better suited for younger children
  • however the new rules do not affect existing models of booster seats and booster cushions - parents can continue to use existing models available -provided that the labelling indicates that they are suitable for their child
  • the key message is to check the label of the backless booster seat (booster cushion) that you are using or looking to buy - if the label shows that it is suitable for the child that you are carrying - you will not be breaking the law

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