UK car seats law: make sure your child’s booster seat is legal

If you are a parent, you know how important it is to have the right car seat to protect your child in the event of an accident. But if you make the wrong choice and you are caught with an unsuitable or incorrectly fitted booster seat, you could find yourself with a hefty £500 fine. If you want to ensure your child is buckled up safely – and you won’t be out of pocket – read our guide on how to choose the right car seat.

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What happens if I break car seat laws?

If you fail to ensure that your child is in the correct car seat, you could face a fine of up to £500 and three penalty points on your licence. This can mean that you are perceived as a higher risk by car insurers and can push up the cost of your premiums.

What is the law on child car seats?

In the UK, a child must sit in a car seat until they are either 135cm tall or 12 years old, whichever comes first. For kids over 135cm in height or older than 12, wearing a seatbelt like an adult is sufficient.

For children who do require a car seat, you can select which seat is appropriate based on their height or weight (more about car seat categories below).

Always ensure that the seat you are buying is EU-approved for use in the UK – just look for a label with a capital “E” in a circle.

In addition to the “E”, the label on approved height-based seats should show “R129” and on approved weight-based seats should show “ECE R44”.

Only an EU-approved car seat can be used in the UK.

What do car seat groups mean?

Car seat groups are based on weight ranges and may overlap one or more of the seat categories.

The car seat group numbers are:

  • Group 0: 0-10kg (approximately birth to 6-9 months)

  • Group 0+: 0-13kg (approximately birth to 12-15 months)

  • Group 1: 9-18 kg (approximately 9 months to 4 years)

  • Group 2: 15-25 kg (approximately 4-6 years)

  • Group 3: 22-36 kg (approximately 6-11 years)

There are some exceptions when a child over the age of three does not need to legally use a car seat:

  • Children over the age of three are legally allowed to use an adult seat belt in a private car if making a short, unexpected but necessary journey 

  • In a taxi or minicab, children must wear a seatbelt and travel in the rear. For children under the age of three, it is safest to travel without a seat belt as it can cause injury in a crash

  • For those that are traveling in a mini bus or coach where a suitable car seat is not available, children must use a seat belt. If there is no adult seat belt fitted, it is safest that kids ride in the back seats 

Does my child need a rear-facing car seat?

All children under the age of 15 months must be rear facing because before this age, their necks are not strong enough to withstand the pressure of a head-on collision in the forward-facing position. Groups 0 and 0+ are rear facing.

Are there special car seat rules for babies?

Many infant car seats come as part of a wider travel system and can be clicked into the pram chassis with adapters. 

However, expert advice states that car seats are for travelling alone and not intended for lengthy naps. The most ideal position for a sleeping infant is laying flat.

According to the Lullaby Trust, babies should not be in a car seat for longer than two hours at a time and they should be taken out frequently.

How long can I leave my baby in a child car seat?

If you will be travelling for a lengthy period of time, it is advised that you stop for regular breaks to allow you to check on your baby and change their position.

The Lullaby Trust charity recommends that ideally, a second adult should travel in the back of the car with your baby, or if you are travelling alone it is helpful to secure a mirror to enable you to observe your child.

If at any time your baby slumps forward, the Lullaby Trust recommends that you immediately stop and adjust their position.

How much do car seats cost?

How much that you fork out on a car seat will vary, with rear-facing and forward-facing options costing anywhere between £50 and £350.

The good news? Car seats can last longer than you would think – often for many years – meaning they can be reused for siblings.

What’s more, they become less expensive as your child gets older. However, keep in mind that plastic can get brittle with age and car seats have an expiry date. 

When in doubt, check for an expiry date sticker and try to avoid anything that could be more than five years old.

Should I buy a second-hand car seat?

While you may be able to bag a bargain by buying a used car seat, be careful. 

The Royal Society for the Prevention of Accidents recommends that you avoid second-hand car seats altogether as you can never be confident that it hasn’t been involved in an accident, even when buying from those you trust.

While you may not be intentionally misled, minor damage can be forgotten or overlooked but still affect the safety of the car seat. 

What if my car seat is stolen or damaged?

If you are in an accident or have had your car seat stolen from your vehicle, you might be able to make a claim on an insurance policy.

However, this type of cover is not always included with a car insurance policy.

According to statisticians Defaqto, nearly a quarter of comprehensive car insurance policies will not compensate you for a replacement car seat.

What's more, those that do pay out in the event of a claim don't offer the same level of cover across the board, with only half of insurers offering a full reimbursement.

What should I look for to ensure my car seat is properly installed? 

If the seatbelt or harness is loose, twisted or appears to sit incorrectly across your child, make sure that you correct the placement before you head off.

During winter months, be mindful to remove your child’s bulky coat before adjusting the slack as the thickness of the material can leave the harness too loose to be effective in an accident.

Car insurance is just one of the costs of keeping your car on the road along with tax, petrol and servicing, so cut your insurance costs by comparing the best deals for you.