Car seat laws in the UK

Believe it or not, seat belts didn’t become a legal requirement for rear passengers until the year 1987. Meanwhile, the use of car seats wasn’t mandatory until as recently as 2006. 

Since then, all infants from birth must, by law, sit in a specially designed car seat until they reach a certain age or height. Failure to do this could result in receiving a hefty fine, or more importantly, risk a potential injury in the event of an accident.

Whatever stage your child may be at, you always want to keep them safe with the right car or booster seat. However, after several updates over the years, the law can be slightly confusing, and it’s difficult to know what kind of seat to use. To help you out, we’ve put together all the rules and regulations you need to know about when your child should use a booster seat.

So, what are the main points of the law? 

  • A suitable child car seat must be used until the child reaches a height of 135cm or 12 years old, whichever is reached first.
  • Children must sit in a rear-facing seat until they are 15 months old. Your child can use a forward-facing child car seat when they’re over 15 months, but it’s recommended to use a rear-facing one for as long as possible.
  • Backless booster seats can only be used by children who weigh 22kg or more. If they weigh less than this, they’ll need to either use a car seat or a high-back booster seat.
  • Booster seats with backs can be used by children weighing between 15-36kg. Again, before they reach this weight, they’ll need to use a car seat.
  • Children over 12 or more than 153cm tall must wear a seat belt.
  • It is the driver's responsibility to ensure that children under the age of 14 years are restrained correctly in accordance with the law.
  • When a passenger is 14 years old or older, it is their own responsibility to ensure they’re wearing a seat belt. 

What car seat do I need for my child?

Firstly, only EU-approved child car seats can be used in the UK and there are two categories to choose from – height-based and weight-based.

The former, known as i-Size seats, are manufactured to the latest EU standard ECE R129, and it’s down to you to make sure your chosen seat is suitable for the height of your child.

Meanwhile, weight-based seats are manufactured under the EU standard ECE R44-04. They offer a range of options, outlined in the table below:
  Group Seats
0kg - 10kg 0 Lie-flat or ‘lateral’ baby carrier, rear-facing baby carrier, or rear-facing baby seat using a harness.
0kg - 13kg 0+ Rear-facing baby carrier or rear-facing baby seat using a harness.
9kg - 18kg 1 Rear- or forward-facing baby seat using a harness or safety shield.
15kg - 25kg 2 Rear- or forward-facing child car seat (high-backed booster seat or booster cushion*) using a seat belt, harness or safety shield.
22kg - 36kg 3 Rear- or forward-facing child car seat (high-backed booster seat or booster cushion) using a seat belt, harness or safety shield.
*Manufacturers can now only make group 3 approved booster cushions. However, this doesn’t affect existing booster cushions in group 2, so you’ll still be able to use them.

Some important things to consider when choosing and fitting your car seat:
  • As stated above, children must sit in a rear-facing seat until they are 15 months old. Don’t be tempted to move a baby to a forward-facing seat just because their feet are pressing against the rear seat of your car. It’s best to wait until they reach the weight limit or the crown of their head reaches the top of the baby seat before you make a change.
  • Never fit a rear-facing child seat in the front of your car where there is an active passenger airbag. The airbag must be deactivated or the rearward-facing child seat must be placed in the back seat of the car.
  • Child seats must be fitted either using ISOFIX mountings or a diagonal seat belt strap.
  • The seat should be secure. If it wobbles, it is either wrongly fitted or not suitable for your car. 

When can my child start using a booster seat?

It’s recommended that your child can start using a booster seat when they reach 4 years old or at least 15kg in weight. Meanwhile, if your child is above 22 kg weight, or 125 cm tall, they can use a ‘booster cushion’, which is basically a backless booster seat, so it doesn’t offer side impact protection. It’s important that they meet these criteria and can be trusted to sit still, as this is the final stage before they can go without and just use the car seat belt. 

While it’s not required by national law, we recommend keeping your child in a high-backed booster seat with an integral harness for as long as possible before moving to a booster cushion.

When can a child travel without a car seat?

Children under 3 must always use the correct child car seat in the front and rear. The only exception is if a child car seat is not available in a licensed taxi or licensed private hire car. This rule was introduced for practical reasons rather than safety, but you should always think about ways to make sure a child seat is available.

Similarly, children aged 3 years and above, until they are either 12 years old or 135cm tall, must use the correct restraint in the front and rear. However, there are some exceptions to this rule as well:  

  • If they are in the rear seats of a licensed taxi, private hire vehicle, coach or minibus that does not have a child seat.
  • If they’re travelling a short distance and the journey is necessary and unexpected.
  • If there are two occupied child restraints in the rear preventing a third one being fitted.
  • If the vehicle is not fitted with seat belts (only applies to vehicles that were originally manufactured without seat belts). 

The same rules apply for children with disabilities or medical conditions, but they may use a disabled person’s seat belt or child restraint designed for their needs. A doctor may issue an exemption certificate if necessary.

Can you put a car seat in the front of a car?

While it is not recommended, it is not illegal to put a car seat in the front of a car. It is safer for children to travel in the rear, and, as mentioned above, you should never put a rear-facing child seat on a passenger seat where an active passenger airbag is fitted. If the child is in a forward-facing seat in the front, the passenger seat should be pushed back as far as possible so that the airbag cannot reach them. 

What age can a child sit in the front seat of a car?

From age 12 and up, children can sit in the front seat without a car booster seat, although a seat belt is required by law.

The UK law does, however, state that children aged 3-12 years old or up to 135cm tall must sit in a booster seat, either in the front or back of the car. The car seat must be suitable for their age and height and they must be wearing a seat belt.

Similarly, children under the age of three can sit in the front seat only if there is no space in the back for a child’s car seat. They must travel with the correct car seat and have the airbag disabled.

While there are several reasons why you may need to let your child sit in the front seat, it’s advised that children sit in the back for as long as possible and you wait until they reach the recommended 12 years of age.

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