What are the benefits of an extended rear-facing baby car seat?

Find out everything you need to know about extended rearward-facing car seats, including if they are safer, and the height and weight limit for a rear-facing toddler car seat
Hannah FoxSenior researcher & writer
Two children in rear-facing car seats

In a front-on collision, extended rear-facing car seats offer a higher level of protection to a child’s delicate head, neck and spine, compared to a forward-facing toddler seat.

Although you can never guarantee what type of collision you would be in, we would recommend opting for an extended rear-facing car seat for as long as possible.

Especially as the most dangerous car accidents are typically frontal collisions, and they’re also one of the most common.


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Best extended rear-facing car seats 

Below we've rounded up the extended rear facing car seats that impressed most in our rigorous lab tests.

To find the best child car seat for your needs, head straight to our extended rear-facing car seat reviews to compare all of the models we've tested.

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Extended rear-facing car seats explained

When a car crashes in a frontal collision, all the occupants continue to move forwards until their seatbelt or harness stops them, holding them in place so they don't hit the inside of the car.

However, this force can cause a lot of strain on the areas of the body held back by the seatbelts, and also on the head and limbs, which are flung forward after impact.

Babies’ bodies are different from adults, as they’re not fully developed. They can suffer severe injuries to their neck, spine and internal organs from the force of a crash, especially if they’re not strapped in properly or are in the wrong car seat.

In a front crash in a forward-facing seat, a baby's neck is subjected to a force equivalent to 300-320kg – that's about 47 stone of weight on a baby's neck.

But in a front crash in a rear-facing seat, the baby’s head is cocooned by the padding and the shell of their car seat, which supports the head and back, limiting the movement of the head on the neck, and reducing the force on the neck.

However not all parents know this. When we surveyed 2,021 parents with a child under the age of five in February 2021, 52% thought it was safest for children to travel facing forwards from nine months old. 

Rear-facing baby car seats offer four types of protection: 

  1. They make sure that a baby’s head doesn't move around, reducing the chance of neck and spine injuries. 
  2. They stop the head banging into other surfaces, such as the car door or window. 
  3. They surround the baby with a protective shell to prevent them from being hit by bits of car, glass or other debris. 
  4. They distribute the pressure from the child restraint as widely as possible over the strongest parts of the body. In an infant, the strongest part of the body is the back.

Compare the scores for all the child car seats we've tested in our child car seat reviews.

Height and weight limit for extended rear-facing car seats

Child in rearward facing seat

R129 car seat regulations state that children should be rearward-facing until they're 15 months old, but we recommend keeping your baby rearward-facing for even longer if possible. 

That's where extended rear-facing car seats come into play, as they are typically suitable from around 12 months old or even birth, and they enable your little one to remain rearward facing until they are 105cm tall for i-Size car seats (or 18kg for R44 car seats), both of which are around four years old.

In fact, there are increasing numbers of seats that allow you to rearward-face for even longer, up to 125cm, which is around five or six years old.

Some of the models that we've tested that do this  include: 

Still not sure what to go for? We explain the difference between car seat weight groups and height groups.

Is there enough legroom in rear-facing car seats?

Although a child’s legs may appear more vulnerable when they're facing the back of the car, the aim of a child car seat is to protect the vulnerable head, neck and internal organs, which are much harder to heal than broken leg bones.

Older children may look squashed in extended rear-facing car seats, but children are much more flexible than adults and can sit comfortably in cross-legged positions.

It might also seem like there’s limited space for their legs, but many rear-facing child car seats can be installed with varying leg space, so that they allow for a very compact installation but can give your child as much room as possible.

Make sure to visit the manufacturer website or refer to the instructions to ensure you’re positioning the car seat correctly to make the most of the space available.

If you’re worried about damaging your car’s rear seats, it’s possible to pick up protective covering to stop dirty shoes from messing the fabric.

Why you should get your extended rear-facing car seat fitted

Boy sat in extended rear-facing car seat
If you do opt for an extended rear-facing car seat, we’d recommend that you have the seat fitted at a retailer that specialises in this type of seat.

We’d also advise you to read the instructions several times and watch installation videos online to be sure it’s installed correctly.

A car seat is only as good as the way it is fitted, and some rear-facing car seats in our tests are so complicated to install that there’s a real risk it could be installed incorrectly and not provide the best protection in a crash.

Go to our guide on how to fit a baby or child car seat for tips and advice on installing your child's car seat correctly.

Video: how to fit an extended rear-facing toddler car seat

Our video will provide guidance on how to fit a toddler car seat that's extended rearward-facing, using Isofix.

Browse all of our reviews covering child car seats suitable for toddlers.

Extended rear-facing swivel car seats

Placing a child in a rear-facing car seat can be a struggle and it can put a lot of strain on your back.

But a number of manufacturers have introduced child car seats with a 360-degree rotation feature that can rotate to any position you choose, making it a whole lot easier to get your little one in and out of the car.

These swivel car seats allow for extended rear-facing, forward-facing and – cleverly – a stop in-between where you can turn the seat towards the door to help you put your child in the seat and buckle them up.

Find out more and which ones we rate in our guide to swivel car seats for babies and toddlers.

Using extended rear-facing car seats in more than one car

Depending on the type of car seat, it will be fitted with the vehicle’s seatbelt or into Isofix fitting points built into the car, if it is an Isofix or i-Size seat.

Alternatively, some rearward-facing car seats come with a separate base, and the base is fitted with the car's seatbelts or into its Isofix points and the child car seat clicks onto the base.

If you will be using your extended rear-facing car seat in more than one car, then it may be worth investing in multiple Isofix bases for your car seat, which stay installed in each car.

This makes it much quicker and easier to swap the car seat between cars as you simply need to pop it onto the base and it’s ready to be used.

What are Isofix car seats? We explain everything you need to know.