UK Car Seat Laws 2025: The Expert Guide with Axkid

The UK follows the United Nations Economic Commission for Europe (UN ECE) regulation R129, however, R44 child car seats can still be sold within the UK. 

Regarding the law, you must use a restraining system and with regards to children, the law states:

• You must not carry an unrestrained child in the front seat
• Children under three travelling in a vehicle must be carried in a correct child restraint (infant carriers or child seat). 

Children must use a child car seat until they’re 12 years old or 135 centimetres tall, whichever comes first. A child over 135cm in height (approx 4ft 5ins) or 12 years old must wear an adult seatbelt, in the front or rear. However, we advise using a high back booster to approximately 150cm tall.

A child car seat can be chosen based on a child’s height or weight. Under UN ECE regulation R129, height-based seats stipulate a child must be rear-facing until 15 months old. A child can use a forward-facing child car seat when they’re over 15 months old. Only EU-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’. 

As advocates of child safety in cars, Axkid recommends always using a child car seat, even on short journeys in a taxi or Uber to ensure the safety of your little one. 

Using the Front Seat: Is It Allowed?  

A child car seat may be installed on the front seat as long as the airbag may be deactivated. If the airbag cannot be deactivated for any reason, then a child car seat cannot be installed on the front seat.  

When Can a Child Stop Using a Car Seat?

Children must use a child car seat until they’re 12 years old or 135 centimetres tall, whichever comes first. Children over 12 years or more than 135cm tall must wear a seat belt.  

Car seat service life

A child safety seat has an approximate service life of ten years, and Axkid recommends using the car seat for no longer than eight years from the date of purchase. A car seat may be stocked at a store for up to two years before it is sold, which is factored into the service life. If you buy a used car seat, you may not know when it was first sold or for how long it was used. Over time, the materials in the car seat can wear and degrade, so replacing the seat after eight years is the safest option.

Testing and safety evolves

Child car seat standards continue to develop and become more stringent. The requirements a seat was tested to in 2008 differ greatly from those in place today. Modern seats are manufactured to meet higher safety standards, giving you confidence that the product has undergone thorough testing.

The car seat’s history is unknown

A used car seat may have been in an accident or have unseen damage that compromises its safety. Because it’s rarely possible to know the full history of a second-hand seat, its condition can’t be guaranteed. Buying new also gives you a warranty and, in many cases, insurance cover if your seat is in an accident.

Spare parts no longer manufactured

As time goes on, older car seats may be discontinued, meaning spare parts or manuals may no longer be available. Without the correct instructions or parts, installing or maintaining the seat properly becomes more difficult. For all of these reasons, purchasing a new car seat gives peace of mind that it meets current standards and is safe to use.

When it comes to car safety for children, parents should be mindful of every stage of their child’s growth and development. One of the most important decisions is when to transition a child from a rear-facing car seat to a high-back booster seat. A high-back booster seat is an important piece of safety equipment, and parents should consider several factors, including the child’s weight, height, and age. 

It is safest for children to remain in a rear-facing car seat for as long as possible, moving to a booster seat only when they have outgrown the height and weight limits of the car seat. Ideally, a child will stay rear-facing for as long as possible, and if the seat allows, this could be until around 6–7 years of age.

To ensure that the booster seat fits correctly, parents can follow the six guidelines outlined below.

1. Stay rear-facing for as long as possible 

Paediatricians and safety experts recommend that children remain rear-facing for as long as possible. Rear-facing car seats protect the child’s head, neck, and spine in a crash. This position is especially crucial for babies and children up to 6-7years, whose head will account for a more significant percentage of their overall weight.  

2. Back against the booster seat  

When the child is ready for a booster seat, it is crucial to ensure they are seated correctly. The child should sit with their back against the booster seat, with no slouching or leaning forward. This position helps the booster seat provide appropriate protection for the child in the event of an accident.  

3. Knees bend at the edge of the seat  

The child’s knees should bend at the edge of the booster seat. If the child’s knees are not able to bend, the seat is too deep and may not provide adequate protection in an accident. Parents may need to consider allowing their child to remain rear-faced for longer or if needed choose a booster seat with a shallower seating area for their child.  

4. Lap belt on top of thighs, not over the soft stomach  

The lap belt should rest on top of the child’s thighs, not over their soft stomach. This position ensures that the child’s hips and pelvis, which are more durable than their abdomen, absorb the force of an impact.  

5. Shoulder belt between the neck and shoulder  

The shoulder belt should fit snugly between the child’s neck and shoulder, without touching their neck or sliding off their shoulder. If the shoulder belt does not fit correctly, parents may need to choose a booster seat with an adjustable shoulder belt.  

6. Sits properly. No slouching, no playing with seatbelts, etc

The child should sit upright in their booster seat, with no slouching or playing with the seat belt. If the child is not sitting correctly, they may not be adequately protected in the event of an accident.  

In summary, when it comes to car safety for children, parents must choose the appropriate seat based on their child’s age, weight, and height. While transitioning from a rear-facing car seat to a high-back booster seat, parents should follow the six guidelines to ensure that their child is seated correctly and adequately protected in the event of an accident. 

Expert Safety Advice from Axkid