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Best car seats for children aged 4+ for 2026
We’ve tested and reviewed the best high-backed booster seats for children aged 4+, including lightweight, compact, premium and great-value options from Maxi-Cosi, Joie, Cybex, Thule, Nuna and more.

- Emily Longman Wall
Published: June 12, 2026 at 2:40 PM
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If your child has outgrown their toddler car seat, they may be ready for a booster seat — usually suitable from around age 3 or 4 until around age 12. There are 2 main types: high-backed booster seats and booster cushions. All of our picks below are high-backed boosters, as they offer more support and protection.
You’ll often see booster car seats referred to as group 2/3 seats, although most newer car seats now adhere to the R129 safety standard, explained below.
To help you pick the best car seat for your child and your car, we’ve tried, tested and reviewed hundreds of car seats and quizzed parents across the UK about the car seats they’ve used as their kids grow. From our reviews, car seat expertise and conversations with parents, we’ve assembled our list of the best car seats for children age 4+.
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Best car seats for age 4+ at a glance
- Best car seat for innovation: Maxi-Cosi Rodifix Pro² i-Size, £169.99 at Boots
- Best value car seat: Joie i-Trillo, £75 £60 at Bundle Baby (Save £15 or 20%)
- Best car seat for advanced safety features: Axkid Up, £399 at John Lewis
- Best car seat for comfort: Cybex Solution T i-Fix, £174.95 £159.95 at Bundle Baby (Save £15 or 9%)
- Best lightweight car seat: Graco Junior Maxi i-Size, £40 £34.99 at Amazon (Save £5.01 or 13%)
- Best car seat for premium comfort: Thule Palm, £219.95 £186.96 at Natural Baby Shower (Save £32.99 or 15%)
- Best car seat for changing temperatures: Silver Cross Discover i-Size, £150 £99 at Amazon (Save £51 or 34%)
- Best car seat for simple installation: Joie i-Traver, £100 at Bundle Baby
- Best car seat for advanced back support: Avionaut MaxSpace AirFlow, £249 at Kiddies Kingdom
- Best car seat for growing with your child: Nuna Aace LX, £220 at Bundle Baby
- Best car seat for abdominal support: Britax Römer Kidfix i-Size Car Seat, £199 £159 at Kiddies Kingdom (Save £40 or 20%)
Jump to:
- Best child car seats from 4 years for 2026
- How the best car seats for children ages 4+ compare
- When do I move to a high-backed booster seat?
- What is the R129 child car seat safety standard?
- What to look for when buying your car seat
How we chose our 11 of the Best
When selecting our 11 best car seats, we considered ease of use and fitting, comfort for child, lifespan, size and weight, safety features and whether each seat is worth the money. All seats on this list have also been tested by experienced parent journalists. Our Best lists rely on a number of sources, including our independent reviews, testing undertaken during the MadeForMums Awards, and feedback from our home testing panel and Top Testers Club. Each year thousands of products are put through their paces by hundreds of parents across the country on behalf of MadeForMums, to ensure we’re bringing you honest and true reviews and recommendations. Our list is not an ordered ranking from 1-11. Instead, it is a carefully selected group of tried-and-tested products, each of which we believe is best for a different situation or requirement. We don’t just tell you what is best, we help you discover what is best for your family.
Compare the best car seats for children aged 4+
Car seatBest forRRPSuitable forWeightDimensionsi-SizeInstallationRecline positionsHeadrest positionsMFM Review Star RatingMaxi-Cosi Rodifix Pro² i-SizeInnovation£169.9915-36kg/100cm-150cm6.24kgH73-79cm x W44-51cm x D42cmYesIsofix or car seatbelt3Up to height 79cm4.9 starsJoie i-TrilloValue£60100-150cm4.43kgH62-83cm x W48-56cm x D40cmYesCar seatbeltNo104.0 starsAxkid UpAdvanced safety features£39915-50kg/100cm-150cm9.55kgH83cm x W43.5cm x D63.6cmYesISOFIXNoneMultiple4.7 starsCybex Solution T i-FixComfort£179.9515-50kg/100cm-150cm7.2kgH62.5-80cm x W50.5cm x D39cmYesISOFIX or car seatbeltMultiple via headrestUp to height 82cm4.4 starsGraco Junior Maxi i-SizeLightweight design£40100cm-150cm3.4kgH60.5-81.5cm x W45.6cm x D39cmYesCar seatbeltNo10 height settings4.1 starsSilver Cross Discover i-SizeChanging temperatures£99100cm-150cm7.1kgH66-81cm x W46-57cm x D31cmYesISOFIX or car seatbelt4104.8 starsJoie i-TraverSimple installation£100100cm-150cm5.6kgH63-83cm x W56cm x D40-44cmYesISOFIX or car seatbelt2104.6 starsAvionaut MaxSpace AirFlowAdvanced back support£24915-50kg/100-150cmNot specified50cm x 49cm x 81cmYesISOFIX or car seatbeltMultipleMultiple4.6 starsNuna Aace LXGrowing with your child£220100-150cm6.7kgH64-85cm x W45-57cm x D43-70cmYesISOFIX or car seatbeltCustomisable174.9 starsBritax Römer Kidfix i-SizeAbdominal support£19915-36kg/100-150cm6.7kgH63-83cm x W48cm x D42cmYesISOFIX or car seatbeltNoUp to height 83cmN/AThule PalmPremium comfort£219.95100-150cm7.14kg45.6cm x 44.8cm x 62.6cmYesISOFIX or car seatbeltMultipleAdjustable4.8 stars
Best child car seats from 4 years for 2026
Maxi-Cosi Rodifix Pro² i-Size, £169.99
Best for: Innovation
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Why we chose it: This innovative high-backed booster offers strong safety features, comfort-led design and plenty of adjustability as your child grows.
This seat has surpassed my expectations with its brilliant safety features, solid structure and soft, cushioned covers. The fact that it offers 3 recline positions, is made from eco-conscious, temperature-regulating materials and adjusts in height and width with your growing child, makes this a fantastic booster seat.
Reviewer Cher, who tested this car seat with her 4-year-old son (pictured)
What we like
- Fabric made using recycled materials
- Extra padding for safety and comfort
- Side-impact protection
- Choice of 3 recline positions
- Grows in height and width
What to keep in mind
- No cupholder
- No arm rests
Key SpecsMaxi-Cosi Rodifix Pro² i-SizeRRP£169.99Best forInnovationSuitable for15-36kg/100cm-150cmWeight6.24kgDimensionsH73-79cm x W44-51cm x D42cmi-SizeYesInstallationISOFIX and seatbeltRecline positions3Headrest positionsUp to height 79cmMFM Review Star Rating4.9 stars
Maxi-Cosi has been a respected name in car seats since the 1980s, and this updated Rodifix Pro² i-Size is packed with thoughtful safety and comfort features.
It includes G-CELL side impact protection, an ultra-padded AirProtect headrest and adjusts in both height and width as your child grows. The expanding side wings, Eco-Care fabrics, 3 recline positions and ClimaFlow technology all help make it a comfortable long-term option.
It’s easy to install using Isofix or a seatbelt and light enough to move between cars. While it doesn’t have arm rests, this can make it easier for older children to buckle themselves in independently.
Read the full MadeForMums Maxi-Cosi Rodifix Pro2 i-Size car seat review
Available from: Boots, Maxi-Cosi, Kiddies Kingdom and Amazon
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Joie i-Trillo, £60
Best for: Value
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Why we chose it: A reliable, affordable high-backed booster with side-impact protection, a good ADAC score and handy child-friendly details.
This car seat is a great buy for someone looking for a lightweight and compact booster seat that should last their child years. It is slimline, perfect for tighter space in the back of the car, and well-made and comfortable.
MFM reviewer Annabelle, who tested this car seat with her 4-year-old son Tadhg (pictured)
What we like
- Affordable
- Shell Grey version made using recycled materials
- 2 retractable cup holders
- Machine washable covers
- Side-impact protection
What to keep in mind
- Doesn’t recline
- Not as padded as some other car seats
- Not Isofix compatible
Key SpecsJoie i-TrilloRRP£60Best forValueSuitable for100-150cmWeight4.43kgDimensionsH62-83cm x W48-56cm x D40cmi-SizeYesInstallationSeatbeltRecline positionsNoneHeadrest positions10MFM Review Star Rating4.0 stars
If you’re looking for a reliable seat at a competitive price, the Joie i-Trillo comes in under £100 but still offers the reassurance of a strong ADAC test score. It has Joie’s Guard Surround Safety panels for extra protection at the sides, as well as side wings and adjustable head support.
The seat is fitted using the car seatbelt, and thanks to its streamlined size it’s possible to fit 3 seats in a row in i-Size approved vehicles, with children up to 135cm in height.
We also like that the Shell Grey colourway is made with 100% recycled fabrics, using 24 plastic bottles. For children, the biggest hit is likely to be the 2 retractable cup holders, which tuck neatly into the seat base until needed.
Read the full MadeForMums Joie i-Trillo car seat review
Available from: Bundle Baby, Boots, Argos and Kiddies Kingdom
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Axkid Up, £399
Best for: Advanced safety features
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Why we chose it: This premium booster combines advanced safety thinking with a foldable, portable design and a patented raisable seat.
The Axkid Up is light to carry, foldable and provides a safe fit and ride for our children. The second-to-none safety features and the unparalleled design makes it absolutely worth the money. As a parent of 4 children, I see this seat as an investment in my children’s safety. It will be used for years to come, no matter what car we are driving.
MFM reviewer Sophie, who tested this car seat with her 7-year-old daughter Tiggy
What we like
- Comfy for child
- Fully adjustable so grows with your child
- Portable — easy to fold and store
- Excellent build quality
- Advanced safety features
- Leg rest and cup holder included
What to keep in mind
- Expensive
- Lack of padding on seat
Key SpecsAxkid UpRRP£399Best forAdvanced safety featuresSuitable for15-50kg/100cm-150cmWeight9.55kgDimensionsH83cm x W43.5cm x D63.6cmi-SizeYesInstallationISOFIXRecline positionsNoneHeadrest positionsMultipleMFM Review Star Rating4.7 stars
A world-first, the Axkid Up has a patented raisable seat, meaning that as your child grows, you can help ensure the seatbelt sits in the safest position at every stage. It genuinely adapts as your child grows, offering a tailored fit to help keep them safe. The ISOFIX base also has a built-in support leg for extra stability, and there are removable side wings you can add too.
The seat folds down quickly and easily, which MFM reviewer Sophie called “game-changing”, making it easy to transport between cars or store when not in use. It’s also the slimmest seat on our list, so it should fit 3 across the back seat in most vehicles — a valuable feature if space is at a premium.
Read the full MadeForMums Axkid Up car seat review
Available from: John Lewis and Natural Baby Shower
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Cybex Solution T i-Fix, £199.95
Best for: Comfort
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Why we chose it: With a clever tilting headrest, strong safety score and ventilation features, this is a comfort-focused choice for longer journeys and naps.
My daughter was very happy in the car seat, and keen to climb in. There's plenty of cushioning on the seat, which she said was nice and soft. She often fell asleep in it, which is a sign that she’s comfy, although not so good for danger naps! I felt reassured by the extra safety features, I am confident that it will last for years and love how smart it looks in my car.
MFM reviewer Hannah, who tested this car seat with her 4-year-old twins (her daughter is pictured above)
What we like
- One-hand adjustment for height and width
- Tilting headrest
- Washable covers
- Ventilation features for comfort
- Good safety credentials
What to keep in mind
- Cup holder needs to be bought separately
- On the pricey side
- Over 7kg, so not the lightest to move between cars
Key SpecsCybex Solution T i-FixRRP£179.95Best forComfortSuitable for15-50kg/100cm-150cmWeight7.2kgDimensionsH62.5-80cm x W50.5cm x D39cmi-SizeYesInstallationIsofix and car seatbeltRecline positionsMultiple via headrestHeadrest positionsUp to height 82cmMFM Review Star Rating4.4 stars
Snoozing in the car is a given for many children, and the Cybex Solution T i-Fix has a patented headrest design to help stop little heads tipping forward while sleeping. This offers comfort during naps and helps keep heads in a secure position when children are awake too.
The seat has a strong overall ADAC rating and offers advanced linear side-impact protection. It’s simple to install using either Isofix or a seatbelt, although at over 7kg it’s not the most lightweight option for swapping between cars.
Designed with comfort in mind, it features a 3D net structure and mesh inserts to improve air ventilation and help keep your child at a comfortable temperature. It also adjusts in height and width with 1 hand and has 12 positions to help it last from young child to pre-teen.
Read the full MadeForMums Cybex Solution T i-Fix car seat review
Available from: Bundle Baby, Cybex, Kiddies Kingdom, Mamas&Papas and Natural Baby Shower
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Graco Junior Maxi i-Size, £40
Best for: Lightweight design
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Why we chose it: A budget-friendly, very lightweight booster with side-impact protection and practical cup holders.
This car seat is amazing value. While it, understandably, doesn't offer the same level of padding or premium fabrics as high-end boosters, this Graco offering is still a comfortable option (no complaints from my children!), with enhanced side impact protection, adjustable headrest and retractable cupholders, at a minimal cost. Plus, the lightweight design means it would also be a great option if you wanted to take a car seat abroad.
MFM reviewer Hannah, who tested this car seat with her 4-year-old twins (her son is pictured above)
What we like
- Affordable
- Side-impact protection
- Retractable cup holders
- Lightweight
- Machine-washable covers
What to keep in mind
- Arm rests aren’t padded
- No Isofix installation
- Not ADAC tested
Key SpecsGraco Junior Maxi i-SizeRRP£40Best forLightweight designSuitable for100cm-150cmWeight3.4kgDimensionsH60.5-81.5cm x W45.6cm x D39cmi-SizeYesInstallationSeatbeltRecline positionsNoneHeadrest positions10MFM Review Star Rating4.1 stars
Packing in plenty of features at a strong price, the Graco Junior Maxi i-Size car seat is a useful option for those on a budget. With advanced side-impact protection, this R129 i-Size car seat still offers key safety features and is suitable from around 3 to 12 years, with a 10-position headrest to adjust as your child grows.
While it isn’t Isofix compatible, the Junior Maxi features open-loop belt guides to help position the seatbelt correctly. What really impresses is how light the seat is, weighing just 3.4kg, making it a good option for moving between vehicles or taking on holiday.
It may not look as premium as some other car seats in our round-up, but the Junior Maxi is still nicely padded and includes 2 retractable cup holders for drinks, snacks and little treasures.
Read the full MadeForMums Graco Junior Maxi i-Size car seat review
Available from: Halfords, Boots, Amazon, Very and Graco
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Thule Palm, £219
Best for: Premium comfort
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Why we chose it: This premium high-backed booster combines plush cushioning, easy adjustability and a slim, practical design that worked well across daily family journeys.
I would recommend it to parents who want a high-quality, long-lasting booster seat that goes beyond the basics. It is particularly well-suited to families who spend a lot of time in the car and want a seat that delivers consistent comfort and support across every journey.
MFM reviewer Maria, who tested this car seat with her 4-year-old daughter Summer and 7-year-old son Parker
What we like
- Exceptionally comfortable with soft PUR-foam cushioning
- Easy-to-adjust headrest for different child heights
- Smart, premium design with wipe-clean arm rests
- Slim design fits well in smaller cars or alongside other car seats
- Secure seat belt positioning with helpful guide clip
- Multiple recline options
What to keep in mind
- Higher price point
- Limited colour options if you prefer brighter designs
- Footrest costs extra
Key SpecsThule PalmRRP£219.95Best forPremium comfortSuitable for100-150cmWeight7.14kgDimensions45.6cm x 44.8cm x 62.6cmi-SizeYesInstallationISOFIX and car seatbeltRecline positionsMultipleHeadrest positionsAdjustableMFM Review Star Rating4.8 stars
The Thule Palm is a premium high-backed booster for children from around 3.5 to 12 years, or 100-150cm. Its soft PUR-foam cushioning, supportive headrest and recline function kept both our 4-year-old and 7-year-old testers comfortable on everyday trips and longer journeys.
It’s straightforward to install with ISOFIX connectors and clear indicators, and reviewer Maria had it fitted in under 5 minutes. Once in place, it felt stable and secure, with a helpful seat belt guide to keep the belt correctly positioned.
Although it’s not the lightest booster at 7.14kg, Maria still found it easy to move between cars, and its slim design worked well in smaller spaces. The standout features are comfort and build quality, with machine-washable covers and wipe-clean arm rests adding everyday practicality.
Read the full MadeForMums Thule Palm car seat review
Available from: Thule, Natural Baby Shower, John Lewis and Very
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Silver Cross Discover i-Size, £99.50
Best for: Changing temperatures
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Why we chose it: This premium-looking booster combines generous padding, temperature-regulating bamboo fabric and plenty of adjustment.
My daughter loves sitting in this seat and regularly tells me how comfy it is! The padding feels very luxurious and the extendable thigh support adds an extra level of comfort. The seat offers all the safety features you’d expect or hope for, making the tradition from traditional car seat to booster feel less nerve-wracking, and has the added bonus of looking great too.
MFM reviewer Sarah, who tested this car seat with her 7-year-old son and 4-year-old daughter (pictured above)
What we like
- Looks good
- Lightweight
- Bamboo covers
- App for easy fixing
- Side-impact protection system
What to keep in mind
- On the pricey side
- No cup holder
- May be snug for children on a higher percentile
Key SpecsSilver Cross Discover i-SizeRRP£99Best forChanging temperaturesSuitable for100cm-150cmWeight7.1kgDimensionsH66-81cm x W46-57cm x D31cmi-SizeYesInstallationISOFIX and seatbeltRecline positions4Headrest positions10MFM Review Star Rating4.8 stars
Silver Cross is known for performance products with a heritage feel, and the Discover i-Size has a premium, diamond-stitched embossed eco-fabric seat in 4 chic colourways.
It isn’t just about style. This high-back booster is generously padded and easy to install using either Isofix or your car seatbelt. The bamboo fabric is a particular plus, offering temperature-regulating qualities that work well all year round.
With 10 headrest positions, 4 recline positions, additional thigh support and removable side wings, the Discover i-Size is designed to grow with your child. Its compact footprint is useful if you need to fit multiple seats in your car, although it may feel snug for larger children.
Read our full MadeForMums Silver Cross Discover i-Size car seat review
Available from: Amazon and John Lewis
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Joie i-Traver, £100
Best for: Simple installation
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Why we chose it: A comfortable, well-padded booster with clear belt guides and straightforward Isofix or seatbelt installation.
It's incredibly straight forward to install and I would recommend it to other parents due to its comfort, competitive pricing, and excellent safety features.
MFM reviewer Georgette, who tested this car seat with her 4-year-old son Jude (pictured above)
What we like
- Adjustable seat depth
- Side-impact protection
- Extra-padded headrest
- Machine-washable covers
- Lightweight
What to keep in mind
- No cup holder
Key SpecsJoie i-TraverRRP£100Best forSimple installationSuitable for100cm-150cmWeight5.6kgDimensionsH63-83cm x W56cm x D40-44cmi-SizeYesInstallationISOFIX or car seatbeltRecline positions2Headrest positions10 height settingsMFM Review Star Rating4.6 stars
Despite its plush, heavily padded appearance, the Joie i-Traver is actually a lightweight choice for swapping between cars, weighing 5.6kg. The cushioning and padded arm rest make it comfortable for children, but it’s also strong on safety.
The i-Traver has Guard Surround Safety panels, a cocooning headrest and cushioning memory foam layers. Its 10-height headrest can be adjusted with 1 hand, even when the seat is installed in the car, and the 3-position seat depth helps provide more room after growth spurts.
Whether you plan on keeping the car seat in one vehicle or moving it around, installation is straightforward using either Isofix connectors or your car seatbelt. The belt guides are clearly marked in green, helping you see exactly where the seatbelt needs to go.
Read the full MadeForMums Joie i-Traver car seat review
Available from: Bundle Baby, Boots, Kiddies Kingdom and John Lewis
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Avionaut MaxSpace AirFlow, £249
Best for: Advanced back support
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Why we chose it: Recognised for healthy back support, this roomy premium booster is designed for posture, comfort and long-term use.
This car seat has been designed to last, and offers unbeatable comfort and protection. The fact that it has recline positions, is comfortably roomy, and made from temperature regulating materials makes it a great choice for parents happy to spend a little bit more in order to benefit from high quality features.
MFM reviewer Cher, who tested the car seat with her 5-year-old son (pictured above)
What we like
- Adjustable headrest and backrest
- Effortless installation
- Stylish
- Longevity of use
- Breathable fabrics
- Multiple recline options
What to keep in mind
- Quite heavy to lift
- Expensive
- Bulky for smaller cars
- Side Impact Protection is tricky to fit
Key SpecsAvionaut MaxSpace AirFlowRRP£249Best forAdvanced back supportSuitable for15-50kg/100-150cmWeightNot specifiedDimensions50cm x 49cm x 81cmi-SizeYesInstallationISOFIX or car seatbeltRecline positionsMultipleHeadrest positionsMultipleMFM Review Star Rating4.6 stars
The Avionaut MaxSpace AirFlow was a hit with our reviewer Cher and her 5-year-old son. The seat has been recognised by the AGR for promoting healthy back support and correct posture, which helped give our reviewer peace of mind that her son was seated safely and comfortably.
The seat also provides comfort through its temperature-regulating AirFlow system, designed to hold heat during cooler months and promote airflow during warmer months. Cher said her son, who can overheat easily, didn’t get sweaty in this seat on a long trip.
Designed to grow with your child thanks to its width, adjustable headrest and multiple recline positions, the seat should provide comfort and safety until your child reaches 150cm or around 12 years of age. It is one of the more expensive seats on our list, but its safety credentials, ergonomic design and quality feel make it a strong choice for families who want a premium booster.
Read the full MadeForMums Avionaut MaxSpace AirFlow car seat review
Available from: Kiddies Kingdom
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Nuna Aace LX, £220
Best for: Growing with your child
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Why we chose it: With 17 headrest positions, adjustable seat depth and custom-fit recline, this is a smart long-term option for growing children.
Although one of the most expensive seats in its category, it's worth the money because the clever 3D Growth™ System means it'll last you until your child no longer needs a car seat, plus they'll find it comfortable even when they're much bigger. The seat is lightweight too so it's very easy to move from car to car. I also found it so easy and intuitive to install and feel happy that my children are as safe as possible thanks to the belt guides and ISOFIX indicators.
MFM reviewer Hollie, who tested the car seat with her 4-year-old daughter (pictured above) and 7-year-old son
What we like
- Grows in height, width and seat depth
- Stylish
- Machine washable covers
- Detachable side-impact protection pods
- Recline options
- Includes cupholder
What to keep in mind
- No armrests
- On the pricey side
- Best for a bigger car at its widest setting
Key SpecsNuna Aace LXRRP£220Best forGrowing with your childSuitable for100-150cmWeight6.7kgDimensionsH64-85cm x W45-57cm x D43-70cmi-SizeYesInstallationISOFIX or car seatbeltRecline positionsMultipleHeadrest positions17MFM Review Star Rating4.9 stars
When it comes to customisable comfort, it’s hard to beat the Nuna Aace LX. Featuring 17 headrest positions, adjustable seat depth and custom-fit recline positions, this smart-looking seat is designed to support children from 4 to 12.
It’s part of the Aace LX’s 3D growth system, where you can easily increase the seat depth and raise the headrest to provide more shoulder width as your child grows. Installation is also simple thanks to the Isofix fitting, green belt path and belt positioner.
Safety features include energy-absorbing EPP foam and detachable side-impact pods to help reduce the force of impact in a collision. The good ADAC rating adds reassurance, while the machine-washable covers are a practical bonus for everyday family life.
Read the full MadeForMums Nuna AACE lx car seat review
Available from: Bundle Baby, Halfords and Kiddies Kingdom
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Britax Römer Kidfix i-Size, £199
Best for: Abdominal support
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Why we chose it: This strong all-round booster stands out for its SecureGuard system, which adds an extra contact point to help protect the abdomen.
I was really nervous moving from a harness seat but this one has a foam pad for the seat belt to help protect the neck and chest and a bit to keep the seat belt from digging into the abdomen and side-impact protection.
Parent tester Cali
What we like
- Comfortable for child
- Washable covers
- Advanced side-impact protection
- Can be fitted with Isofix or vehicle seatbelt
What to keep in mind
- Doesn’t recline
- Expensive
Key SpecsBritax Römer Kidfix i-SizeRRP£199Best forAbdominal supportSuitable for15-36kg/100-150cmWeight6.7kgDimensionsH63-83cm x W48cm x D42cmi-SizeYesInstallationISOFIX or car seatbeltRecline positions0Headrest positionsUp to height 83cm
This high-back booster is made in Germany by Britax, a brand with 50 years of research and experience behind it. It’s a strong all-round booster with ventilation panels, removable fabrics and advanced side impact protection, and it can be fitted using either Isofix connectors or your vehicle’s seatbelt.
Its standout feature is its lap belt rest, which sits in the optimal position across your child’s pelvic bone. The SecureGuard system fits between your child’s legs, effectively adding a 4th contact point to a 3-point seatbelt to help protect the abdomen.
There’s also a shock-absorbing foam pad over the chest, designed to reduce the impact of any jerky head movements.
Available from: Boots, Very, Kiddies Kingdom, Natural Baby Shower
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When do I move to a high-backed booster seat?
Car seat standards are generally based on height and weight suitability rather than age, so exactly when you need to move your child into a high-backed booster seat depends on which growth percentile they are on. The seats in this list are often referred to as being suitable from around age 4, but it can depend on the model.
It can be tempting to move to a booster seat as quickly as possible as they tend to be lighter and less bulky than toddler seats, but there is no rush to move your child out of their toddler seat if they still fit. If your toddler car seat has extended rear-facing capabilities, it makes sense to take advantage of that for as long as you possibly can.
Toddler seats also have a 5-point harness that offers more support for small bodies than the seatbelt used to fasten a booster seat. Some newer seats suitable for toddlers — such as the Axkid One 2 and the Axkid Minikid 3 — can be used until they reach 25kg in weight, which can be age 6 or 7. There’s no need to change before then if your child still fits safely.
What is the R129 child car seat safety standard?
While the term “group 2/3 seats” is still in use and may already be familiar, it refers to the older R44 legislation. Most child car seats, especially newer ones, now comply with the newer R129 safety standard.
The R129 standard follows more detailed tests for improved head and neck protection. R129 seats also go through side-impact testing and Q dummy crash tests with 32 sensors. Because it focuses on a child’s height, rather than just weight, it gives a more accurate guide on the safest time to upgrade a child’s car seat.
What to look for when buying your car seat
Fitting
Car seats either fasten using the car seat belt or Isofix connectors that click into your car’s frame. Some may also have a tether strap. No one method is safer than another so long as the seat is fitted correctly, but many people find Isofix more convenient and straightforward, and therefore less prone to error. You will need to check the cars you use have Isofix connectors in the right place if you want to use an Isofix seat.
Safety
Safety is the key issue for any car seat. The big change for this age group is that most car seats no longer have a built-in harness. Instead, the child is secured using the adult seat belt, which will also thread through the car seat in some way. All car seats in the UK will have been tested to one of two European standards: ECE R44/04 or the newer ECE R129. R129 seats have been tested for side impact as well as front and rear impact collisions.
Longevity
The law requires that children up to 12 years old or 135cm in height must use a child car restraint where seat belts are fitted. This means you’ll be using this seat for a long time, so consider how it adapts and grows with your child.
Weight
Car seats vary significantly in weight. Some are under 5kg, while others weigh around 8kg or more. Think about how often you’re going to remove it from the car or move it between vehicles. If you’re likely to keep switching it around, a super lightweight booster may suit you best. A heavier seat may feel sturdier, roomier and more comfortable, and may offer more extended safety features.
Portability
A carry handle may be useful if you’ll be moving the seat around a lot. Some seats also fold, which can be handy if you need to stash it in the boot or take it on holiday.
Ease of installation
Once you’ve done it a couple of times, installing your car seat should be quick. Read the instructions thoroughly, as each car seat will be different. If you are using only a seat belt, make sure the seat feels secure and doesn’t wobble or move around.
Comfort
A comfy seat generally means a happier child, especially on long journeys, so consider padding, cushioning and head support. Some seats are wider for comfort, but may be harder to fit in your car, especially if you need 3 seats in a row. Ventilation systems, recline positions and comfortable headrests can all help on longer trips.
Coverings
If you’d like the option to wash messy covers, look for removable covers that can go in the washing machine, rather than simply sponge-clean fabrics. Also consider fabric finish: a natural bamboo cover, for example, may feel less sweaty. Colour choice may also matter if you want a seat that fits your car interior or your child’s preferences.
Extra functions and details
Some car seats include cup holders, in-built headrest speakers, extra recline positions, leg rests or other comfort features. Think about what will make a real difference to your child and your daily routine.
Price
Car seats can vary widely in price depending on features, fabrics and accessories, but most of the seats on our list are between £100 and £250. A higher price point doesn’t necessarily mean a safer or more secure seat, but some premium seats have been tested beyond the legal requirements or include extra comfort and convenience features.
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Authors

Emily Longman WallDigital Content Producer
Emily is the Digital Content Producer at MadeForMums, where she writes, edits and produces editorial and video content across the brand. She independently curates the weekly editorial newsletter, leads product review commissioning and oversees the brand's awards programmes, working with parent testers and experts to bring trusted recommendations to families. She specialises in car seats and pushchairs and has yet to meet a buggy she couldn't fold! With a First Class Honours degree in History, she loves getting stuck into research and making complex information accessible to parents.
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