Child car seats: How to buy
How to choose the right size seat
Choosing the right seat always starts with your child’s weight – use our table to find the right size. Your child’s weight is the deciding factor; the ages given are just a guide. Here is our guide on which size you should be buying:
As your child grows
It's safest to buy a specific child seat to suit your child's weight as they grow, rather than try to buy one that covers the whole weight range. Try to keep the baby in the lower group seat as long as you can, but make sure you don’t leave it until they're over the weight limit before changing.
Buy a specific child seat to suit your child's weight as they grow
This means you should use a Group 0+ baby seat up to at least 10kg, then consider changing to a Group 1 seat, which they will use until they are at least 15kg.
At 15kg (about 3-4 years), start thinking about changing to a Group 2/3 seat, which will suit the child all the way up to age 12, when they should use the adult seat belt.
Weight and height
While the child's weight is the primary factor to consider when choosing an appropriate seat, we're sometimes asked about the relevance of a child's height to the seat. In most cases, the child will reach the weight limit before being too tall for a seat.
However, your child will have outgrown the seat if their eyes are level with the top of the seat. If they're below the thresholds suggested above, seek advice from a qualified child seat expert (contact your local authority road safety office to find out who this is in your area). In extreme cases they may advise you seek advice from a medical doctor or paediatrician.
Protecting premature babies
We regularly receive queries about car seats for pre-term babies. We asked Farid Bendjellal, Technical Director at Britax about this. He told us: ‘For pre-term and newborn babies, lying flat is ideal for comfort and to reduce the chances of apnia (respiratory problems). But for crash protection, near-vertical is ideal – however, this presents a risk of apnia. Hence a compromise of around 45 degrees is usually chosen for Group 0+ seats.’
Carrycots
We've tested several carry cots and lie-flat seats, and until now, we haven’t found any that protect satisfactorily. However, in our latest tests, we tried the Britax Baby Safe Sleeper, a new lie-flat restraint designed to carry your newborn baby lying down. It is the first we've seen that protects well in both front and side crashes, and even though it is quite complicated to install, its clear instructions and warning labels mean there's little danger of installing it incorrectly. In fact, it scores well enogh in all our assessments to be awarded Best Buy status.
You should always place it across the back seat, as close to the middle as you can. This may use up more space, but it means the baby is less vulnerable in a crash. Place the baby’s head as far from the door as possible, to try to avoid contact with the door in a crash.
Consult your doctor before transporting a pre-term baby by car, and keep travel times to a minimum for all newborns.
Child car seat as part of a travel system
Try the seat in your car with your child before you buy
Some child car seats can be removed from the car and placed in a travel system. Group 0 and 0+ car seats are most commonly sold as part of travel systems.
A travel system pushchair can be used with a compatible car seat and/or carrycot that's designed to attach to the pushchair. They let you easily transfer your baby between car, pushchair and home – great if you spend a lot of time on the move. But be aware that babies should not spend long periods of time in a child car seat.
Travel systems appear to be a bargain because they're flexible, but the pushchairs are often large and heavy and you need space to store parts you’re not using. Babies will outgrow the child car seat in around 12-15 months.
Multiple group seats
All child car seats are categorised according to the child's weight. As a child's bone and body structure dramatically changes during the first few years, what's needed from a safety restraint also changes.
Some seats span different groups. At 15kg (3 to 4 years old) you can change to a Group 2/3 seat, which will suit the child all the way up to age 12, when they should use the adult seat belt.
But we’ve found that generally, seats designed to span more than two groups are too much of a compromise in at least one weight group and we haven’t found any Group 1/2/3 seats worth recommending.
Beware of boosters
Some Group 3 products are just booster cushions. These raise the child's body to a height suitable for use with the adult seat belt, but the booster cushions are not as safe as Group 3 seats with a full length back and 'wings', which provide extra protection for the head and chest in a side-impact crash.
The booster cushion satisfies the new legal requirement for kids up to 4ft 6in, and they're cheap (about £20-£30) but the full child car seats are safer – if more expensive.
Choosing a child car seat
- Make a list of the cars in which you might use the seat – for example, friends’ or grandparents’, as well as your own.
- Use our Best Buys as a starting point for choosing a seat.
- Find out if a seat will fit in a particular make/model of car – check with the seat manufacturer and the car manufacturers for compatibility for use of the seat with the cars in your list.
- If you know which seats you're interested in, try them in your car with your child before you buy. If your child isn’t yet born, try the seat in your car anyway. Don’t wait until the baby is born – unless you have a child car seat, most hospitals won’t discharge you if you're travelling home by car.
- Take advice from a qualified adviser. This is, for most of us at a retailer – a good one will find seats that suit the car or cars you’ll be using it in, and show you how to install it properly. Some areas (like Bromley and Essex), have special centres where you can seek advice and try out seats.
Universal seats
There’s no such thing as a truly universal seat yet. Because the belts and the passenger seats in cars differ greatly from model to model, some seats work better in some cars than others – check with the seat manufacturer to make sure the seat you are considering is suited to the cars you want to use it in.
And you can’t assume your Isofix car will suit all Isofix seats – some cars have a false floor which won't work with a support leg, for example.
Second-hand
Never buy a second-hand seat – it could have been in crash which will have weakened it.