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The best car seats for four-year-olds

• The best car seats for four-year-olds
• Car seat groups and ISOFIX explained
• What safety features do you need?

Written by Eleanor Weaver Updated: 17 October 2023

If you’re here, we’ve no doubt that your child has outgrown the car seat they’ve had since they were a baby. With baby/toddler car seats best suited up to the age of three or four, you’ll be in need of a top-notch car seat that can fit their fast-sprouting frame and continue to grow with them through primary school.

In the UK, it’s a legal requirement for your little one to use a car seat until they are 12 years old or 135cm in height, whichever comes first, and with our pick of the best car seats that’ll last up to this age, you won’t need to fork out on this car essential again.

What car seat should a four-year-old be in?

When looking for a car seat for your four-year-old, you should be looking for their ‘stage group’ based on their weight, rather than their age. The stage groups for kids are broken down as follows under ECE R44 regulations.

• Group 0+/1/2 car seats: Is suitable from birth to 25kg, approx. 6-years-old.

• Group 1/2/3 car seats: Is suitable for children 9-36kg, approx. 9 months to 12 years.

• Group 2/3 car seats: Is suitable for children 15-36kg, approx. 3 to 12-years-old.

• Group 3 car seats: Based on new safety regulations launched in 2017, group 3 car seats i.e. new booster seats on the market, are limited to children who are taller than 125cm, and weighing more than 22kg.

If you’re buying a new car seat for your four-year-old, you’ll want to buy a Group 1/2/3 car seat or Group 2/3 car seat depending on their weight when they outgrow their baby seat.

Four-year-old in car seat

Car seat safety features

It’s recommended that you should try to keep your child in the lowest stage group for as long as possible to give them the optimal safety features, and there’s no need to swap for the next stage group up until your child has outgrown their Group 1 car seat. These are the safety features you’ll find in the optimal car seats for four-year-olds:

Multi-stage car seats (Group 1/2/3)

Also known as combination car seats, these have been designed to carry your child from baby to the booster-seat stage and as a result, they come with an initially much higher cost but really are great value for money. These car seats are equipped with padding and a five-point harness.

High back booster seats (Group 2/3)

These car seats are designed to lift your child up to use the vehicle seat belt but come with a high back and side padding for safety and impact protection.

i-Size car seats (Height-based system)

You’ll find a number of car seats described as ‘i-Size’, but what does this mean?

Expected to eventually be adopted across all new car seats sold, i-Size was introduced in 2013 as safety regulation ECE R129 with rigorous testing through impact crash trials and new state-of-the-art Q dummies to test impact. Using a height-based system, i-Size car seats have been designed to take the guesswork out of choosing the right fit, provide better protection from side impacts, and keep children rearward-facing for longer, until at least 15 months or 75cm to protect their fragile heads and necks.

If you’re after optimal protection for your little one, this is the type of car seat to go for but again, they come at a higher cost.

What is ISOFIX?

You’ll hear this term bandied about too, and it’s a fab feature to look for in your kid’s car seat. Why? Because it’s a doddle to fit and will keep your little one’s car seat safely secured.

isofix

ISOFIX compatible car seats have two arms that lock onto small metal bars located in the seat of your vehicle to anchor the car seat into place. No seat belt threading is necessary and they’re accompanied by install indicators so you can be sure it’s correctly connected.

Most new cars have a pair of ISOFIX anchor points and since November 2014, all new cars are legally required to have ISOFIX fitted. But, it’s definitely something worth checking for in your car if it’s an older model and you want to reap the benefits.

Parkers pick the best car seats for four-year-olds:

Available in a bunch of colours, the Cybex Gold Pallas G i-Size Child's Car Seat grows with your child to provide optimum support, protection, and comfort to keep them safe from 15 months until approx. 12-years-old. Talk about going the distance! Tested to the UN R129/03 latest standard, it provides over 40% less strain on the neck whilst the impact shield helps reduce the risk of neck injuries in a frontal collision when compared to a harness system. And don't worry, when they get too big, this can be easily removed.

Pros

  • Suitable from 15 months to 12 years
  • Prevents strain on the neck
  • Impact shield is better than harness

Cons

  • Initially expensive - but will pay for itself in time
This Stage Group 1/2/3 car seat is another great choice of longevity, providing three seats in one to grow with your child and at an affordable price. With just one hand you can adjust the headrest to 10 height positions, and the Grow Together™ headrest and harness system adjust simultaneously - making it easier for parents to strap little ones in. It's packed with safety features such as full side impact protection plus Guard Surround Safety panels, but this one isn't ISOFIX compatible.

Pros

  • Three seats in one
  • Adjustable headrest
  • Range of safety features

Cons

  • No ISOFIX
The Cybex Aton 5 is well made and is a great child car seat that provides a good overall level of protection when installed into a car using the Isofix base. It's also a travel system compatible with a range of Cybex pushchairs. Some of the unique safety features include the height-adjustable headrest with integrated harness guides, and there's an integrated XXL fold-away sun canopy giving UPF 50+ protection.

Pros

  • Easy to fit with clear instructions
  • ISOFIX
  • Linear Side-impact Protection

Cons

  • Quite an old design now
Super cute and comfortable with a range of fun designs, the Cosatto Zoomi Car Seat is suitable from 9-36kg and can easily be converted to a high back booster seat when the time comes. The Zoomi grows with your child with an adjustable height and headrest, and an anti-escape system with a five-point harness included to keep little ones from wriggling free.

Pros

  • Can convert to a booster seat
  • Five-point harness
  • Adjustable headrest

Cons

  • More features found elsewhere
If you're looking to get a new car seat for your growing four-year-old, the Halford’s Group 2/3 Highback Booster Seat is suitable from 15kg (approx. 4-years-old) and is very affordable. It has Side Impact Protection, an adjustable headrest, a simple three-point seat belt installation, and even has a retractable cupholder for their favourite drink (or snacks!) on the move.

Pros

  • Affordable
  • Adjustable headrest
  • Cup holder!

Cons

  • Restrictive use due to tight group criteria
  • Three-point harness only
The Maxi-Cosi Rodifix Air Protect car seat is suitable for approx. three-and-a-half to 12-year-olds and incorporates a load of innovative features. In the event of a crash, their patented AirProtect® side-impact protection will divert forces away from your child's head by releasing air embedded in the foam headrest device upon impact. The seat also provides optimal protection for the body and hips and a comfortable, simple-to-adjust seat to suit your child's length and width.

Pros

  • Patented AirProtect system
  • Simple to adjust
  • Suitable for three-and-a-half to 12 years

Cons

  • Some users have noted the foam is squeaky
This i-Size car seat has a secure seat belt installation system and three layers of protection; the Tri-Protect headrest with memory foam, Guard Surround Safety panels, and ISOFIX connectors. Your child will be nice and comfy on the move with the padded armrests and it's fully adjustable to suit their growing body.

Pros

  • Tri-Protect headrest
  • Good safety features
  • Nice padding for comfort

Cons

  • Uses car's seatbelt instead of a harness
This sturdy high-back booster from Cybex comes locked and loaded with built-in side impact protection, a Patented reclining headrest, ISOFIX, an 11-position height-adjustable headrest, and an adjustable backrest. Available in six colours, we don't think your little one will struggle to take a snooze in one of these.

Pros

  • Great protection
  • Comfortable features
  • 11-position headrest

Cons

  • Wide base takes up room in smaller cars
This basic and affordable option is highly rated by parents and grandparents alike on Amazon. With height-adjustable armrests and headrests, it provides side impact protection and the thrill of retractable cupholders for your child. Plus, the cover is machine-washable for any spillages that happen as a result - inevitable if you ask us.

Pros

  • Affordable
  • Great backup seat
  • Cup holders!

Cons

  • Basic for everyday use
Perfect for three-year-olds and up, this travel buddy has seven different height positions that can be adjusted using just one hand (ideal if you're juggling other little menaces). The seat comes packed with protection with the Guard Surround Safety side-impact panels for full-body impact protection and ISOSAFE connectors.

Pros

  • Easily adjusted
  • Good protection

Cons

  • Not as robust as other options

Can a four-year-old use a booster seat?

We haven’t included any booster seats for four-year-olds as it’s unlikely your tot will be big enough to use one at this age.

Based on new safety regulations launched in 2017, group 3 car seats i.e. new booster seats on the market, are limited to children who are taller than 125cm and weigh more than 22kg. The average height and weight of a four-year-old in the UK fall below these requirements.

Previously, these car seats were approved for use by children weighing between 15-36kg, but they’ve been deemed by the UN as being unsuitable for protecting smaller children from side-on collisions due to the reduced safety features.

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