How to Choose the Right Booster Seat for Your Child

Mum and two daughters taking selfie in the boot of car with suitcase

When your child reaches a certain age and size, a standard baby or toddler car seat may not be right for them any longer. In these cases, a booster seat is the required option instead – according to UK law, children must use car seats until they are either 12 years old or reach 135cm / 4ft 5in in height, whichever comes first.

In this short guide, we’ll look at some of the different things you should be aware of when picking out the right booster seat for your child.


What’s the law for car seats in the UK?

A booster seat is basically a cushion seat with no back that can be used for toddlers and children weighing between 15 and 36kg. Booster seats help to raise children’s heights slightly, so they can safely use an adult seatbelt without any issues.

According to UK child’s car seat rules and regulations, children should be using booster seats until they are 12 years of age or reach 135cm / 4ft 5in in height – whichever comes first. Once they exceed this height or are older than the age of 12, they will no longer be required to use a booster seat. The age on booster seats is for the safety of the child.

It’s important to be aware of the rules and regulations around child car seats. Car seat rules in the UK are categorised into different groups, which take into account the weight, height and age of your baby or child. You may be able to choose from more than one type of seat in the group for your child’s weight, as some combination seats cross over different groups.

These laws have been created with the safety of the baby or child in mind. The correct use and fitting of all car and booster seats is of paramount importance so that they are most effective in the event of an accident. A car seat is one of the biggest investments you will make when it comes to the safety of your child, so it’s extremely important to be aware of the rules that surround this so you are able to make the right choice.


How to choose the right size booster seat

Picking out the right booster seat is an important task, and so it requires careful thought and planning. Car seats in the UK fall into different groups based on the height, weight and age of your child. The requirements for each group will vary based on how old your child is, how tall they are and how much they weigh. Let’s take a look below at the different car seat groups there are available to help you determine which is the best booster seat for your child.



Child's weight

Age of child


Birth up to 10kg/22lb

Birth up to 6 to 9 months


Birth up to 13kg/29lb

Birth up to 12 to 15 months

0+ & 1

Birth up to 18kg/40lb

Birth up to 4 years


9-18kg / 20-40lb

9 months to 4 years

1 & 2

9-25kg / 20-55lb

9 months to 6 years


15-25kg / 33-55lb

4 to 6 years

1, 2 & 3

9-36kg / 20-79lb

9 months to 6 years

2 & 3

15-36kg / 33-79lb

4 to 12 years


When finding the booster seat perfect for your child, there are several different things you should keep in mind, such as the specific height, age and weight of your child. This is probably the most important thing to consider, closely followed by which types of booster seats are compatible with your car. We have a range of booster seats available here at Asda for you to take your pick from – just take a look at our range today.


Types of Car Seat

With so many different options available when it comes to booster seats and child car seats, we understand it can be tricky to wrap your head around it all. To help you better understand the different types available, we’ve put together a quick list to help you out:


  • Infant carriers from birth to 12/15 months – babies of this age should opt for a Group 0+ car seat as they need one that is rear facing which is the safest way for them to travel. These car seats feature a carry handle for easy transportation and have a curved base for gentle rocking and are often pushchair compatible. Many car seat models from this group can be used with Isofix settings so you don’t need to use a seatbelt.
  • Infant/toddler combination seat from 0 – 4 years – if you want to use your child’s car seat for a long time, you can select a Group 0+/1 combination seat until they are 18kg/up to 105cm in height. This style is approved across the two categories and car seats in this combination group can be easily adjusted as your child grows. Most models will have a reclining mechanism for added comfort and come with features including padded, washable seat covers that can be easily removed.
  • Toddler/child combination seats for 9 months – 12 years – this combination of Group 1/2/3 car seats are a long-lasting option that adapts as your child grows and can even be converted to a high-back booster seat, which is ideal for older children until they are able to safely use a seatbelt. These car seats have a cushioned seat and support to keep your child safe and comfortable.
  • Child seats and high back boosters for 4-12 years – these Group 2/3 car and booster seats are designed specifically for older children until they are able to use an adult seatbelt. They are adjustable in height and come with width and leg rest options, as well as fun features such as cup holders or speakers in the headrest.


What is ISOFIX?

Isofix is the name given to an internationally standardised car seat fitting system designed to give you the ultimate peace of mind when driving with young children and babies. This market-leading car seat safety system is built around rigid connection points, which helps secure the child car seat into your car and creates a simpler, more secure installation.

With Isofix, the child’s car seat fastens to the frame of the car seat itself. The rear seats of most modern cars have a pair of anchor points, which connect to a separate Isofix base (usually sold with the child car seat), which creates a strong and secure connection. The child car seat then fastens to the Isofix base, so you don’t need to use a seat belt to fasten the child car seat into the car.


What are i-Size Car Seats?

i-size is a European safety standard for baby and child car seats, and will eventually replace the old safety regulations. To be able to use an i-Size car seat properly, your car must have Isofix connectors available.

i-Size car seats are selected by using the height of your baby or child. A key difference with these seats is that babies will be rear-facing for longer, as this is known to be much safer for them for a number of reasons, particularly the fact that a baby lacks strength in their neck muscles. All i-Size car seats are rear-facing up until the age of 15 months old. I-Size car seats come in three different sizes:


  • 0-85cm – rear-facing baby carrier or baby seat using a harness
  • 0-105cm – rear-facing baby seat until your child is at least 76cm, then forward facing
  • 100-135cm – forward-facing child seat


Impact Shield Technology

Impact shields – or safety cushions as they are sometimes known – fasten around the front of your child when they are seated in a car seat, and act like a pre-inflated airbag. It helps to reduce strain on key areas of the body, spreads and absorbs the forces that are generated during a collision and overall, helps to keep your child safe during an accident. They are particularly helpful when you are unable to use a rear-facing child car seat.


How to install a booster seat?

 Depending on the booster seat you choose to invest in, it will need to be installed and set up in your car in different ways. Both backless and high-back booster seats can easily be fitted in the rear seats of the car and should always be held in place with a safety harness. The booster seat laws in the UK state that children must use car seats and booster seats until the age of 12 or until they are 135cm in height. The booster seat age has been created specifically to ensure all children are as safe as can be whilst riding in any vehicle.

To correctly install a booster seat, place the seat directly in line with the car seat. The seat belt of your car goes around the child and the booster seat itself and can be threaded through the slots found on the booster seat. The seat belt should go across the child’s pelvis, chest and shoulder and should be worn as tight as possible.

If the booster seat has an adjustable back or headrest, this should be adjusted to fit the height of the child using it.

For more specific booster seat requirements, check the instructions they sometimes come with on how to set them safely and securely up in your car.


Tips for buying a baby car seat

Picking a car seat for your baby or child is an extremely important decision when it comes to the safety of your child. Here are some of our top tips on buying a baby car seat:


  • Try out the car seats you like in your car before you actually make a decision to see whether they will fit and work properly in your car. Find a retailer who is willing to help you out with this – some staff may be also trained in fitting car seats and will have tips and advice for you.
  • Check whether your car has Isofix connectors built into it, as they are designed to make it easier and simpler to fit car seats in. Most modern cars will have them – they can be found hidden in the gaps between the padding of your car seats.
  • If your child/baby is likely to travel with other family members/friends in their car, make sure the child’s car seat fits properly into their car as well.
  • Choose a child car seat that’s right for your baby/child’s current height and weight – nothing bigger or smaller.
  • Some car seat manufacturers actually have online car seat guides that show you which cars their seats fit best in, which can help you make a more informed decision.
  • Try to avoid buying a second-hand car seat as it could be damaged or have parts missing. If a family member or friend tries to pass one to you, only accept it if you know it’s in the best condition, not too old and comes with instructions.
  • All car seats in the UK must be EU approved – those that are will have an “E” label somewhere on the seat, which will tell you this.


Do booster seats have anchors?

 Not all booster seats come with anchors – or even the ability to be anchored, but you will find some do if you want your child to have some added support and safety. Anchoring your child’s booster seat has many benefits but must be done very carefully and according to the manufacturer’s instructions.

Taking all the above points into account when trying to pick out the right booster seat for your child will allow you to make an informed decision.




What’s the law for car seats in the UK?

Car seat laws in the UK states that any child that is under the age of 12 and/or under 135cm tall must have their own car seat. It is also recommended that children use a rear-facing car seat until they are at least 15 months old as they are still quite vulnerable to forceful impacts at this age and so require the additional protection that a rear-facing car seat will provide.

A child that is over the age of 12 and/or over 135cm tall does not require a car seat, but they must wear a seat belt at all times.


What car seats are for what age?

Car seats are divided into three main groups, which take into account the height, weight and age of your baby or child. The groups for car seats are as follows:


  • Group 0+ - this is for babies up to the age of 15 months or babies who weigh up to 13kg (29lb), who should be using a rear-facing car seat.
  • Group 1 – for babies and children aged between 9 months and 4 years, who weigh between 9 and 18kg (20-40lb), both rear and forward-facing car seats are suitable.
  • Group 2/3 – for children who are aged from 8 – 12 years and weight between 15-36kg (33lb – 5st 9lb), a rear or forward-facing high-backed booster seat is suitable.


When can my child ride without a booster seat?

Children who are over the age of 12 and/or taller than 135cm do not need to use a booster seat when riding in a car. Child car seat rules dictate that any child who is either younger than 12 years of age or shorter than 135cm are legally required to sit in a car/booster seat when in a vehicle.


Can a child sit on a parent’s lap in the car?

Car seat laws in the UK state that any child that is under 12 years old or under 135cm tall must be in an appropriate car/booster when riding in any vehicle. There are very few exceptions to this rule – if there is no appropriate car seat available, then they must use a seat belt that is fastened securely. Children should not be sat on a parents lap when riding in a car.


Can a child sit in the front seat with a booster seat?

Child seat laws state that children of any age can travel in the front seat of a car provided they do so in the proper, appropriate car seat for their age/height/weight. However, it is generally safer for them to ride in the rear of the vehicle.


Can I take my child in a car without a car seat?

According to GOV.UK, the only time a child older than 3 years is allowed to travel in a back seat without a child car set or a seat belt is if the vehicle does not have one. Children under 3 must always be in a car seat.

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