Car seats

In the UK:

• Children must normally use a child car seat until they are 12-years-old or 135cm tall, whichever comes first
• Children over 135cm tall can use the adult seatbelt 
• It is the driver's responsibility to ensure children under 14-years-old are using the correct restraint.

Child car seats are approved to safety standards based on either a child's heigh or weight:

• Height-based seats must be rear-facing until your child is over 15-months-old. Only approved height-based child car seats can be used in the UK. These have a label showing a capital ‘E’ in a circle and ‘R129’
• Only approved weight-based child car seats can be used in the UK. These have a label showing a capital ‘E’ in a circle and ‘ECE R44’.

For more information about child car seat rules, visit: Child car seats: the law.

Choosing the right car seat is important for your child’s safety. A child seat should be suitable for the child’s height and weight and be compatible with the vehicle(s) it will be used in.

Car seats can be fitted using the vehicle seatbelt or ISOFIX attachment points. Many car seats now use ISOFIX attachment points, which can make installation easier and reduce the risk of fitting errors. Check your vehicle handbook to see whether your vehicle has ISOFIX points.  

Always:

• Choose a seat that meets current safety standards (R129 or R44)
• Follow the manufacturer’s guidance on height and weight limits
• Check that the seat is compatible with the vehicle(s) it will be used in before purchasing. Consider all vehicles the seat may be used in, such as grandparents’ cars
• Register your seat with the manufacturer to receive any product safety updates and recalls
• Consider carefully before using a second-hand child car seat. See guidance below. 

Never:

• Choose a seat based on age alone
• Assume all car seats fit all vehicles.

Using a second-hand child car seat is not generally recommended because it can be difficult to know its history. A seat that has been involved in a collision may have damage that is not visible, which could affect how well it protects a child in the event of a crash. Instructions might also be missing, making it harder to fit and use the seat correctly.

Only consider a second-hand seat if you are completely confident that:

• It has never been involved in a collision
• You know its full history, for example, it comes from a trusted family member or friend
• It includes the original instructions
• All parts are present and undamaged
• It meets current safety requirements and is suitable for your child's height and weight.

Never:

• Use a seat if you are unsure of its history
• Use a seat without the correct instructions.

Rear-facing seats provide greater protection for babies and young children because they support the head, neck and spine in the event of a collision.

It is recommended that children are kept rear-facing for as long as their seat allows, within the manufacturer’s height and weight limits. Extended rear-facing seats can allow children to travel rear-facing until around four years and beyond.

A child car seat cannot provide full protection if it is not fitted and used correctly. 

Always:

• Read and follow the vehicle handbook and the child seat instructions
• Check that the seat is fitted securely before travelling
• Make sure harness straps are tight enough and fitted correctly
• Ensure the harness or vehicle seatbelt lies flat and is not twisted
• Secure your child every journey. 

Never:

• Leave harness straps loose
• Use accessories that were not supplied or approved by the manufacturer
• Make alterations to a car seat.

As children grow, they may move from a child seat with a harness to a high-back booster seat or booster cushion, which helps position the adult seat belt correctly. RoSPA recommends the use of high-backed booster seats, as they offer better protection in the event of a crash.