Written by Alison Williams, edited by Laura Westerman, fact-checked by experts from Good Egg Safety. Published 5 March 2019, updated 4 April 2019
Deciding which car seat to buy for your little one is a big decision to make – and rightly so. It can also be pretty confusing, with many different options to choose from.
So how do you know which baby car seat is best for you and your baby and what do you need to consider before buying one?
Familiarise yourself with car seat safety and regulations
First things first – you’ll need to get to know the typical safety features and the car seat regulations in play. This is so you can make sure that the seat you buy protects your baby in the event of an accident.
Jan James, Chief Executive of Good Egg Safety, who specialise in providing safety advice for families, says that the biggest priority when it comes to car seat safety is to make sure your seat fits your baby and any cars it will be used in, and is installed correctly in the vehicle.
1. Postnatal recovery
The Professional Network of Pelvic Obstetric and Gynaecological Physiotherapy (POGP) have recently warned that lifting and carrying first-stage baby car seats could be detrimental to postnatal recovery as they aren't well designed for carrying and can be heavy, particularly with a baby inside.
Carrying a car seat during recovery – at a time when lifting should be minimal – could lead to pelvic organ prolapse. As such, it is recommended that car seats aren't removed from the car for at least six to eight weeks after birth.
When it comes to solutions, the POGP suggest carrying your little one to the car in a baby carrier or wheeling your car seat to the car on a lightweight frame. You could also get someone else to lift and fit the car seat for you.
It is a legal requirement to rear face babies in R129 child seats until they are at least 15 months old. This is because it is much safer for them. Although you can turn them forward-facing in R44/04 seats a little earlier, child safety experts do not recommend it.
You must always use a car seat if you have a baby in the car with you, even if you’re only driving a short distance.
It is safer to position your child’s car seat in the rear of your car. It is illegal, not to mention extremely unsafe, to fit a rear-facing car seat in the front passenger seat with an active air bag in place.
It’s really important to ensure that your child is in the correct stage of seat for their age, height (R129) or weight (R44/04). Too small or too big could compromise their safety. Please don’t be in a rush to move them up until they reach the maximum limit detailed on the side of the seat. It’s best to make the most of each stage so your child has the chance to mature first. Snug is good!
You should never modify your car seat to make it fit into your car.
Children’s car seats can be fitted using a lap and diagonal seat belt or an ISOfix fitting. If correctly installed, both are equally safe.
With ISOfix, however, there is less margin for incorrect seat fitting which is very reassuring for parents and carers. With either method of installation, it is important to check the seat is fitted correctly and securely for every journey.
Watch this video from Good Egg Safety on how to correctly fit an infant car seat:
Ask the right questions
Not all car seat retailers – even accredited ones – get it right. Nick Lloyd, Acting Head of Road Safety for The Royal Society of the Prevention of Accidents (RoSPA), recommends that, when choosing your baby car seat, you go to a retailer with trained car seat fitters (ideally with car and child, if possible) rather than buying online.
A trained expert will show you how to fit the seat and you should also be able to give it a go yourself, under their guidance. It’s important that every adult using the car seat knows how to use and fit it.
You should challenge anything an expert says that you don’t feel is right – and do make sure they ask you the following:
- Your child’s weight – baby car seats have a weight limit
- Your child’s height – i-Size car seats have height limits
- Your child’s age – this will determine if you need a rear-facing seat (highly likely if your baby is less than 15 months old)
- Your vehicle make and model, plus other vehicles the seat might be used in – some seats don't fit some cars and if it doesn't fit, it won't perform as it should
- If your vehicle has ISOfix – only for an ISOfix car seat
- If your vehicle has underfloor storage – some car seats may not be suitable in cars with underfloor storage. Always follow the vehicle and car seat manufacturers' advice
- If your seat has a top tether – this is a piece of seat belt material with a hook on the end that is attached to the designated anchor point behind the back seat
Read Good Egg Safety's car seat safety assessment form – this is given to retailers to ensure the right questions are asked.
What is ISOfix?
ISOfix is a structural system built into the car that has fitting points to attach an ISOfix car seat. The seat is latched onto the ISOfix points and then braced by using either a support leg or top tether.
You can only use an ISOfix seat in a car with ISOfix fittings and not all vehicles have them, especially older models. It is important to check the child car seat manufacturer’s compatibility list as there are some vehicle features that can make the child car seat incompatible.
You’ll be able to find out if your car has ISOfix attachments by looking for tags or labels in the base of the seat or contact your manufacturer.
An i-Size car seat (see below) will only fit in a car that has ISOfix fittings.
4. Collision and side-impact testing
Car seat laws require all car seats to comply with ECE R44/03 or ECE R44/04. You’ll see an ‘E’ label, with a capital E in a circle, on the seat.
This means that every seat is subject to frontal collision testing at a speed of 50km/h. Only rear-facing seats undergo rear impact collision testing at 30km/h.
Seats complying with ECE R44/04 must also go through a rollover test. These tests are carried out using dummies that represent the weight category of the child approved for a particular seat group.
Claire Waterhouse of Child Seat Safety says that, while under ECE R44/04 there is no requirement to do a side-impact test, some manufacturers do make seats that have this safety feature. You should look for it regardless as well as the seat’s overall crash test rating.
Side-impact protection, to prevent serious head injuries, absorbs the force of the impact in the event of a crash, which means less strain on your newborn’s spine, neck and muscles. This usually takes the form of squidgy padding round the sides and headrest, but some models also have a stabiliser, helping to absorb the force of impact as well.
Under the Road Traffic Act, you can use a seat which has the old standard of R44/03, however these seats will be at least 13 years old and the life span on a seat of this age is only around six years.
As a parent, it's essential that you choose a car seat that had performed well in crash tests.
5. What are i-Size car seats?
i-Size car seats are height-based. i-Size is a new European car seat safety standard that came into force in July 2013 and forms part of the ECE R129 regulations. It aims to increase the safety performance of all child car seats and has raised the minimum testing standards – some manufacturers were already exceeding minimum testing requirements with their R44 seats, however.
iSize is regarded as being ‘safer’ because it eradicates incorrect fitment into an iSize-ready car. iSize seats are automatically compatible with iSize cars.
While the collision testing speeds are the same for i-Size car seats as they are for seats that fall under ECE R44/04, including a rollover test, there are also side impact requirements. Testing is carried out using a ‘Q’ dummy which represents the height, not the weight, of the child.
i-Size makes travelling safer for babies and children – the seats are also easier to fit than regular weight-based designs as they use ISOfix fittings. An i-Size car seat will only fit in a car that has an ISOfix system in place.
At the moment, both i-Size and R44 car seats are available, but eventually i-Size will replace ECE R44 and become mandatory in the UK and Europe – this move will also allow all seats to fit into all cars.
Differences between R44 and and R129 (i-Size):
- Seat classification is based on weight
- No side-impact tests required
- Seat can be fitted using seat belt or ISOfix
- Seat classification is based on height
- Side-impact tests required
- ISOfix-only seats
- Will eventually have belted seats
6. Five-point harness or impact shield?
The main job of a five-point harness is to protect your child if there is an accident. These harnesses work differently in an impact depending on whether your child is in a rear- or forward-facing seat. A baby should be rear-facing until they are 15 months old.
A traditional five-point harness attaches above each shoulder, on both sides of the waist and between your child’s legs. The harness will restrain them, pushing them back into the seat, spreading the force of the impact through the seat, and supporting their head, neck and spine.
Styles vary, with some manufacturers creating automatically adjustable harnesses (when you extend the headrest).
For a harness to be an effective restraint system, it must be buckled correctly – you should only be able to get two fingers between the strap and their collarbone and they mustn’t be able to wriggle their arms out of the harness.
The harness should also be the correct height, sitting as level with the shoulder as possible (although dipping slightly below is fine).
An impact shield is held in place using the car’s standard three-point seatbelt. The child is restrained in the seat but their arms are less restricted as they are not held down in the same way as in a harness.
In the event of a collision, the child’s body curls over the impact shield, dissipating the forces across the whole of the top of the body and therefore reducing the force taken by the neck and spine.
Seats with impact shields are forward-facing only, so can only be used with children from 9 kg.
All seats have pros and cons. Research is important for them all, not just impact shields.
Look at the different types of baby car seat
The types of baby car seat
Most car seats are divided into groups based on weight, with the exception of i-Size. The newborn baby car seat groupings are:
1. Group 0 (0-10kg or 0-22lb) – from birth to approximately six to nine months
- These seats are smaller and lighter than toddler car seats
- Some of these seats are designed to be attached to a pushchair chassis so that you can take your baby from car to pram without waking them – simply attach the car seat to the travel system (double check that they’re compatible before you buy though) and away you go
- Have carry handles, which also act as a rebound bar in a front or rear collision, ensuring the seat doesn’t rock
- May come with a newborn insert to make it a more snug fit for even the tiniest of travellers
- May come with a built-in sunshade
- Don’t last as long as Group 0+, i-Size or Group 0+/1 car seats
2. Group 0+ (0-13kg or 0-29lb) – from birth to about 15-18 months
- Will last longer than a Group 0 seat
- Portable – many have a carry handle and also easily attach to a pushchair chassis
- As such, they can come as part of a travel system
- Can require a base, which costs extra
3. i-Size (by height from approximately 40cm to 105cm) – from birth up to at least 15 months, but in some cases up to four years
- Connect to ISOfix connectors, which reduces the chance of any fitting errors
- Are guaranteed to fit any i-Size-ready car
- Offer better side-impact protection
- Not age-specific
- Make it mandatory for babies to sit in a rear-facing position until they are 15 months old to stop parents looking to forward-facing car seats too early
- Also make it easier for you to keep your child in a rear-facing seat for up to four years (in some cases longer)
- Can be pricey, especially if you have to buy a separate ISOfix base.
4. Group 0+/1 (0-18kg or 0-40lb) – a combination car seat that can be used from birth to approximately four years old
- A combination of Group 0 and Group 1, or Group 0+ and Group 1 seats
- Can be a good investment for some parents – they are rear-facing until your baby weighs 10, 13 or 18 kg depending on the seat, or can be used forward-facing depending on the type of seat you buy
- Larger than a Group 0+ car seat and are designed to stay in one car
- Quite heavy and not especially easy to transport or switch between cars
What else to consider when buying a baby car seat
1. Make sure the seat is comfortable
While safety should be a first priority, you should also make sure your baby is comfy and snug in their car seat, especially if you plan to go on longer car journeys.
Look for good leg support, a roomy seat and an adjustable headrest. An adjustable headrest is essential for combination car seats (group 0+/1 here) to ensure the seat is safe and will grow with your child. Most child car seats also have headrests with a set recline to ensure your child’s head remains within the safety of the padded headrest and doesn’t roll forward when they inevitably nod off.
Small babies sitting upright in a car seat shouldn’t stay in the car seat for longer than two hours as breathing could be compromised. For newborns under four weeks old, this should only be for a maximum of 30 minutes.
2. Is it portable and easy to use?
Is the car seat designed for one car only? Can it be switched between more than one car and it this easy to do? Is it lightweight or heavy and does it have a comfortable handle for carrying?
Check how easy it is to fit in the car, especially if you’ll need to use it in more than one vehicle and assess how easy it is to strap or buckle your little one into the seat. The last thing you’ll want is a fiddly harness that’s tricky to master.
Some models offer a 360-degree swivel function that makes it easier to get your baby in and out of the car seat.
3. How much should I spend?
Prices for car seats can vary enormously, ranging from £40 to over £400.
While all car seats have to pass the minimum safety criteria of regulation R44/04 to be legally sold, many of the bigger brands do their own independent tests at higher speeds, and a lot of the larger car seats that are rear facing-only, have passed the Swedish Plus Test, which is the world's strictest car seat test. These tests cost a lot of money, which is reflected in the price of the seats.
Consider your budget and talk to the retailer about the different tests and standards of each seat – they should be able to advise you.
4. Do car seats expire?
Your car seat should have a label or a sticker with an expiration date. If you can’t find one, then have a look in the user guide or handbook. The expiration date can vary from seat to seat, but is usually between five to 10 years from the date of manufacture.
This doesn’t mean that once you reach that date you should throw the seat in the bin though. It is a recommendation rather than a rule.
As Margaret Bolt, a qualified Child Seat Safety Adviser and founder of Rear-Facing Toddlers explains, "It isn’t a case that the seat will suddenly become less robust or less likely to withstand an accident, but, as a seat gets older, it becomes more difficult to know its history.
It may have been passed from owner to owner, its crash history might not be known, instructions may be missing or spare parts unavailable.
New seats come out all the time with new safety features, new technology and new innovations. This means that the top-of-the-range seat you bought five years ago may no longer be the safest option on the market."
Margaret also advises that, if a new baby comes along, it may be a good idea to considering buying a new seat if your current one is around 10 years old.
5. Are second-hand car seats safe?
As well as being somewhere for your child to sit while you're driving, a car seat's main job is to protect them. And for that purpose, it tends to be a single use item.
In other words, you can use a car seat until you have an accident, but as soon as that happens the seat has to be thrown away and replaced. Even if the seat looks fine, it may have suffered invisible damage that has made it weak and unsafe, so you can’t risk using it again.
A second-hand car seat isn’t necessarily unsafe though. Using a second-hand car seat that was given to you by a relative or a friend that you know they bought new and haven't had an accident with is fine. But if you buy a seat from someone you don’t know, you have no real way of knowing the seat’s history and you could be putting your child at risk.
Good Egg Safety recommend never buying a second-hand seat, even though it may be a cheaper option, in case there is damage from a previous collision or even from something as simple as being dropped.
6. How easy is the car seat to clean?
Nothing’s ever squeaky clean when children are involved, so you’ll want a car seat with removable and washable covers that you can easily shove in the washing machine when you need to.
Ready to shop? Check out our baby car seat reviews before you buy.
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All prices correct at time of publication
Photo credit (images 1 and 2): Good Egg Safety CIC
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