Buying Guide: How to choose the best car seat, plus reviews

What are the new child car seat rule changes for 2017?

Keeping the precious cargo safe

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CHILD CAR seats are a legal requirement in the UK for children from birth until they are 135cm tall or 12 years old, whichever comes first. In some European countries the minimum height is 150cm, which is closer to the average height of a 12-year-old.

The sheer number of different child seats can be daunting, and the last thing a parent wants to do is buy an inappropriate seat or fit it wrongly. New, stricter rules that came in on March 1, 2017 may leave parents even more confused about what type of seat is appropriate for their child.

This guide will help to clarify the rules and legal requirements of child car seats and provide the essential details about the different types.

Why is the right child car seat so important?

For parents, keeping children safe and protected is, of course, essential. Child car seats are designed to reduce the risk of injury in the event of a collision, but thousands of parents in the UK are using the wrong type of seat, or fitting it incorrectly, putting their child at risk.

The road safety organisation Brake says more than 700 children under eight are killed or seriously injured on British roads every year. The figure for under-16s is about 5,000, according to the AA.

Surveys by car seat manufacturers suggest parents experience confusion when it comes to buying car seats and best practices. In 2015 the child seat manufacturer Britax found that nearly 15% of parents didn’t know when to move their child up to the next stage or group of seat, and 22% would incorrectly change simply to make more space in the car.

There’s further confusion about travelling in taxis or friends’ cars (see the laws, below), and almost a third of UK parents with children under the age of 11 (32%) admit they have driven children without a legal child seat.

What are the child car seat laws in the UK?

With some exceptions (see below), using a suitable child car seat or booster seat is a legal requirement every time a child less than 135cm tall and 12 years old travels in a car. Whether you’re a parent or guardian, a relative or even a friend of the family, if it is your vehicle, you’re responsible.

There are three principal rules you should be aware of when it comes to child car seats:

  • Children must normally use a car seat or booster seat until they’re 135cm tall or 12 years old, whichever comes first
  • You must use an EU-approved car seat in the UK. These are identified with a label and capital “E”
  • Child car seats can be purchased based on your child’s height or weight

Height-based car seats (i-Size)

The i-Size standard grades child seats by height and includes stringent European safety regulations introduced in July 2013. These seats are designed for children from birth to 105cm (approximately four years old) and must be rear-facing until the child is 15 months old; after that they may be forward-facing.

They all have Isofix connections that lock securely onto the frame of your car (click here for more information about Isofix), and some may have additional support legs or top tethers.

There are no groups for i-Size seats – they’re just based on the height of your child.

Weight-based car seats

Child car seats are also graded by the weight of the child. While i-Size is considered the future of child car seat regulation, the weight-based seats are still regarded as safe. Some have Isofix connections, but others are secured with the car’s seatbelt, tethers or a combination.

UK law splits weight-based seats into four groups:

Child’s weight Car seat
0kg-9kg Lie-flat or lateral baby carrier, rear-facing baby carrier or rear-facing baby seat with a harness
0kg-13kg Rear-facing baby carrier or rear-facing baby seat with a harness
9kg-18kg Rear-facing or forward-facing baby seat with a harness or safety shield
15kg-36kg Rear-facing or forward-facing child seat (high-backed booster seat or booster cushion), with a seatbelt, harness or safety shield

Some seats can span several of these categories. For example, some are suitable from 0kg to 18kg, so it’s possible to collect your newborn baby from the hospital in a seat that might last them until they’re four years old. See the types of seat below for more details.

Are there any occasions when a child car seat is not required?

Yes, there are exceptional circumstances in which a child doesn’t have to be sitting in the appropriate seat.

  1. Taxis and minicabs

If the driver hasn’t provided the correct car seat, your child is still permitted to travel but only in the back seats of the car. If they are:

  • Three years old or older, they must use an adult seat belt
  • Under three years old, they must travel without an adult seat belt
  1. Minibuses, coaches and vans

It isn’t a legal requirement for minibus, coach or van companies to provide your child with a suitable child car seat. If you want to guarantee one is fitted, you will need to provide it.

  • Coaches: children can travel on coaches without a car seat or seat belt, if unavailable.
  • Minibuses: all children must sit in seats behind the driver if a child car seat or an adult seat belt isn’t fitted. If they’re over three years old it is illegal not to use a child car seat if a suitable one is provided. If one is not provided, it is illegal for them not to use an adult seatbelt.
  • Vans: the rules are the same as for cars.
  1. Unexpected journeys

If you need to travel somewhere unexpectedly with your child and the correct child car seat isn’t available, the rules depend on their age.

  • Three years old or older: you can strap them in with just an adult seat belt as long as the journey is unexpected, necessary and over a short distance.
  • Under three years old: they aren’t permitted to travel without a child car seat unless it’s a licensed taxi and they travel on a rear seat without a seat belt.
  1. No room for a third seat

This is a common problem for parents, for example when giving their child’s friends a lift. Some cars have space for three child car seats side-by-side but most do not. In this situation, the rules again depend on age.

  • Children under three: must travel in the front passenger seat with the correct child seat. Important: do not forget to switch off the passenger airbag, as deployment against a child car seat can result in serious injury.
  • Children aged three or older: can sit in back seat using an adult belt.
  1. Vehicles without seatbelts

Modern cars all have seatbelts but some classic cars do not, particularly ones made before 1966, and manufacturers were not required to fit rear seatbelts until 1987. There is no legal obligation to retro-fit seatbelts to classic cars. Here’s what you need to know about travelling with children in a car without seatbelts:

  • A child aged three or older may travel in a back seat without a car seat and without a seat belt if the vehicle doesn’t have one.
  • However, if the child is under three years old they must be in a child car seat and if there’s no seat belt, they can’t travel.

Booster seat rule changes for 2017

As your child grows they may feel more comfortable sitting in a backless booster seat, also known as a booster cushion. They’re popular with parents, too, as they’re much easier than a full-size child seat to transfer from car to car. But what does the law say?

The old rules said that any child weighing 15kg or more (roughly four years old) could use them but new legislation, that came into force in March 2017, states that new backless booster seats are only approved for children taller than 125cm or weighing more than 22kg.

This means that once a child has grown out of their Group 1 seat, at around age four, parents should look at buying a Group 2/3 high-backed car seat, which can be used all the way until age 12, although some products allow you to remove the back from the seat when your child reaches the 125cm or 22kg.

The new legislation only applies to models manufactured after March 1, 2017, though, so if you already own a backless booster, using it is still within the law.

Why has the booster seat law changed?

Child car seat experts say that booster cushions are unsuitable for small children as they aren’t held as securely in the seat, the adult seat belt isn’t suited to their smaller torso, allowing the child to slip free in a frontal impact accident, and they offer zero protection in a side-impact crash.

Child car seat manufacturer Britax highlighted the safety concerns in 2015 with a campaign called “Bin the Booster”, and released the following crash test footage that compares a booster cushion with a high-backed child car seat:

Research by Halfords earlier this year revealed that 35% of parents surveyed weren’t aware of any changes to the law and more than 40% didn’t know what the proposed changes were. Halfords says it is fully behind the new legislation and is offering 20% off high back seats when customers trade in a booster cushion.

Fitting a child car seat or booster seat

When fitting a weight-based car seat, you must attach it using a diagonal (three-point) seatbelt. This is unless:

  1. The child car seat is specifically designed for use with only a lap belt, or
  2. The child car seat can be fixed with Isofix (see below) anchor points

The law also requires you to:

  1. Deactivate the passenger airbag before fitting a rear-facing baby seat in a front seat (the switch is usually inside the passenger door, on the side of the glovebox, but refer to your car’s owner manual for details).
  2. Not fix a child car seat in a side-facing seat.

What is Isofix?

Isofix is a type of connection between a child car seat and the car that was invented by Britax in collaboration with Volkswagen. Since it was introduced in 1997 it has become an international standard.

All cars manufactured after 2011 have Isofix points fitted between the seat cushion (squab) and the seat back in the rear of the car. Some car makers fitted Isofix to their cars before 2011, though, and Isofix can be found on the front passenger seat on some cars, too.

Prongs on the child seat click into metal loops that are welded to the car’s chassis, creating a strong and rigid connection between the two. An additional top tether (a belt the goes from the child seat over the top of the car’s rear seat and hooks into a connection in the seat back) or support leg can be used to prevent the child seat from tilting or rotating.

Some seats with Isofix points may also require fitting using seatbelts, particularly if your car doesn’t have a top tether point. Read the manufacturer’s instructions for proper fitting instructions.

Isofix is not only seen as the most secure way to fit a child car seat but also the simplest. Isofix seats have been shown to greatly reduce the chance of incorrect fitting.

Be aware that some child car seats with Isofix connectors may not be approved for use in all Isofix cars. The child seat manufacturer’s website should have a list of cars for which their seats are approved.

For more information, click here.

Types of child car seats – which one do you need?

Different types of child car seats are available, of course, tailor-made for all ages and sizes, from newborns through to children aged up to 12-years-old.

Type of Child Restraint Weight / Height Approx. Age Range
Rearward-facing baby seat Group 0
0 – 10kg (22 lbs)
Birth to 6-9 months
Group 0+
0 – 13kg (29 lbs)
Birth to 12-15 months
Not based on weight, but check child’s height is within the range for the seat
Up to at least 15 months
Combination seat
(Rearward and forward-facing)
Group 0+ and 1
0-18 kg (40 lbs)
Birth to 4 years
Group 0+, 1 & 2 (55 lbs)
Birth to 25 kg
Birth to 6 years
Forward-facing child seat Group 1
9-18 kg (20 – 40 lbs)
9 months to 4 years
Group 1, 2 and 3
9 – 36 kg (20 – 79 lbs)
1 to 12 years
High-backed booster seat Group 2
15 – 25 kg (33 – 55 lbs)
4 to 6 years
High-backed booster seat Group 2 and 3
15 – 36 kg (33 – 79 lbs)
4 to 12 years
Booster cushion (manufactured before March 2017) Group 2 and 3
15 – 36 kg (33 – 79 lbs)
4 to 12 years
Booster cushion (manufactured before March 2017) Group 3
22 – 36 kg (48 – 79 lbs)
6 to 12 years
Booster cushion (manufactured after March 2017) 125-135cm and 22 – 36 kg (48 – 79 lbs) 6 to 12 years

What are 
i-Size seats?

i-Size child car seats comply with the latest European safety regulations, introduced in July 2013. They’re designed for children from birth to 105cm (approximately four years old).

  • Must be rear-facing until your child is 15 months old, but can be forward-facing after this age.
  • Offer great all-round safety.
  • All have Isofix connections.
  • There are no groups for i-Size seats – they’re just based on the height of your child.

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What are weight-based Group 0/0+ infant carriers?

Infant carrier seats are easily transportable between your home and car. They’re designed for newborns and those up to 12 months old (or 13kg/29lbs).

  • Should be fitted in a rear-facing position.
  • Fitted with a carry handle for easy transportation of your child.
  • Often compatible with pushchairs.
  • Fitting would involve the adult seat belt or an Isofix base.

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What are weight-based Group 0+/1 “combination” child car seats?

Combination child car seats are designed to be rearward facing from birth to about 13kg, and then can be switched to forward-facing from 9-18kg.

  • Offer good value as they may be suitable up to around your child’s fourth birthday.
  • Children are secured in the seat using an integral harness.
  • May include a recline function for easier sleep.
  • For a more secure installation, an Isofix base is advised.
  • Note: for safety reasons, experts believe children should be rear-facing for as long as possible.

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What are weight-based Group 1 child car seats?

Group 1 seats are suitable for toddlers, from 9kg (approx. 9 months old) to 18kg and are generally forward-facing.

  • Good comfort for children who have grown out of their infant carrier.
  • Offer recline setting, allowing children to sleep more easily.
  • Many are Isofix compatible.
  • Note: for safety reasons, experts believe children should be rear-facing for as long as possible.

Find the best forward-facing car seats on Amazon
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What are weight-based Group 1/2/3 forward-facing child car seats?

Some child seats for children from 9kg to 36kg (up to 12 years old) have a high back with an integral harness.

  • These seats offer good value as they may be suitable until your child no longer needs a child seat.
  • Must be fitted in the forward-facing position.
  • The harness should be applied until the child is 15kg (or 4-years-old). The adult seat belt can then be used.
  • Highback child seats may be fixed with Isofix and/or the car’s seatbelt.
  • Note: for safety reasons, experts believe children should be rear-facing for as long as possible.

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What are weight-based Group 2/3 booster seats?

These child car seats are designed for older children, typically those between four and 12-years-old (or between 15kg and 36kg in weight). They may or may not have a high back and your child is held in place using the car’s adult seatbelt.

  • These booster seats help to raise children, so the adult seat belt can be used.
  • Many models are Isofix compatible.
  • Models with a backrest provide vital support in the event of a collision.
  • The backrest may be removed for larger children (from December 2016 they must be over 125cm tall and 22kg).

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