Child Car Seat Buyer's Guide (15-36kg)

Everything you need to know about child car seats

Babies seem to grow so quickly, it probably feels like you only have to blink and it's time for bigger clothes, new shoes and even a new car seat.

Once you know it's time to take the next step to keep your little one safe in the car, there's still the task of finding the best car seat. We've rounded up some top tips and advice for you to help make the whole thing a little easier so your family can be back enjoying the open road in safety and comfort.

Child car seat safety

Child car seats are essential as regular seats and seat belts are not designed for the smaller size of a child’s body, so won’t offer the same comfort or protection.

Car seat law outlines that children need to travel in an appropriately sized seat until they're 12 years old or 135cm (150cm in ROI) in height, whichever comes first. That means you’ll need to upgrade your car seat as your child gets older and bigger, as not all car seats are designed to span the full 12 years. While baby and toddler car seats will take care of your child when they’re younger, you’ll need a larger child car seat to take care of them through to the point when they no longer need a seat.

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Child car seat sizing

When it comes to car seat sizes, there are two systems commonly used: R44 and i-Size. R44 regulated seats are grouped based on weight while i-Size seats are defined by a child’s height.

R44 (weight based) seats

Within the R44 weight-based system, child car seats are designed for children from around 15 to 36kg, which is groups 1, 2 & 3 and 2 & 3:

Group Child's weight Age of child
0 Birth up to 10kg/22lb Birth up to 6 to 9 months
0+ Birth up to 13kg/29lb Birth up to 12 to 15 months
0+ & 1 Birth up to 18kg/40lb Birth up to 4 years
1 9-18kg / 20-40lb 9 months to 4 years
1 & 2 9-25kg / 20-55lb 9 months to 6 years
2 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

i-Size seats

i-Size seats were introduced in 2013 and use a height-based sizing system. Within the i-Size regulations, seats must undergo an extra side-impact test that isn’t included under the R44 regulation. All i-Size seats are also compatible with ISOFIX systems, making it easier to attach the seats into a car.

i-Size seats come in three different sizes, each of which has a rough equivalent within the R44 sizing system:

  • 0-85cm (approximately G0+ in weight-based system) – rear-facing baby carrier or baby seat using a harness
  • 0-105cm (approximately G0/1/2) – rear-facing baby seat until your child is at least 76cm, then forward facing
  • 100-135cm (UK)/150cm (ROI) (approximately G2/3) – forward-facing child seat

Multi-stage car seats

Multi-stage seats are a great option as they span multiple groups.

They are designed to adapt as your child grows with some designed to be used from birth through to 12 years old when your child no longer needs a seat.

Adapting these seats as your child grows is easy and most will come with adjustable headrests and harnesses, so you’re getting a baby, toddler and child’s car seat all in one!

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Booster cushions and seats

Booster seats are also an option.

There are two main types of booster seats available: backless booster cushions, which are lighter, and high-back booster car seats, which offer more security and support.

A high back booster car seat will give a better level of side impact protection in the event of an accident, and the height adjustment ensures that the seatbelt is fitted correctly over the child. Booster cushions do come with a clip that allows seatbelt adjustment, but this is not as easy to fit and position. The headrests on a high-back booster car seat will also help to keep the child safely in the seat if they do fall asleep.

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What to look for

Here’s a few things to consider when choosing a child car seat:

  • Seat fitting - does the seat attach using the seatbelt or ISOFIX?
  • Convenience - how easy is it to secure the seat and child in place?
  • Multi-stage seats - many car seats are designed to span multiple size groups and can be adjusted as your child grows.
  • Side impact protection - i-Size seats undergo side-impact testing and many i-Size car seats have special side-impact protection technology.

Car seats at Halfords

Hopefully, you now feel a bit more clued up on the best car seat for you. However, we have lots of fully trained, RoSPA-accredited staff members throughout our stores who will be more than happy to guide you through this big decision.

To make it really easy for you to choose the right car seat for your little one, we have also broken down all the features of our car seat range into the following categories:

Simply look out for these icons when choosing your car seat to ensure you're getting all of the features that are important to you.

If you’re still unsure and would prefer to talk this through with one of our experts, contact us on Live Chat where we can offer more advice.

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