Booster Seats In Cars: The Guide



As a parent, how often do you double up as a taxi driver, taking your kids to school, clubs, and parties? How many places do you go a week that involves getting them all in the car – the supermarket, the park, their grandparents’ houses?

The road is a dangerous place for all travellers, because even if you have full control of your own vehicle, you cannot be responsible for the conduct of other road users. It is especially dangerous for children because standard seatbelts are not designed to protect bodies their size.

Between 2016-2018, 1,883 children aged 0-15 were killed or seriously injured in road traffic accidents in England. However, fitting a suitable car seat to your vehicle can help reduce the risk of injury quite significantly. For this reason, it is the law in the UK that children must use a car seat or a booster seat until they reach the age of 12 or aheight of 135cm – whichever comes first. The only exceptions to this are if the child is travelling in a taxi or on public transport, if the journey is an unexpected or emergent one, or if there is no room in the car for another seat.

Let’s take a look at the different types of car seats first, to make sure you are using the correct one for your child.

What type of car seat should I be using?

That depends on how old your child is. All infants and young toddlers should ride in rear-facing seats until they outgrow them. Manufacturers will state height and weight limits in the product information leaflet that comes with your car seat. Most rear-facing seats can accommodate toddlers up to 2 years old.

Once your child exceeds one or both of these limits, they should travel in forward-facing seats with either a three- or a five-point harness to secure them. Again, they should remain using a seat of this kind until they have outgrown it. Forward-facing seats with harness clips are suitable for older toddlers and pre-schoolers. Specific height and weight limits vary from seat to seat, but as a general guide, they should be fine to carry children weighing up to 30kg, and sometimes even more.

When your child has outgrown their forward-facing seat, they’re ready to be upgraded to a booster seat. Booster seats in cars are the types of car seat we want to zoom in on in this article to make sure you have all the facts.

For example, did you know that children seated in booster seats in the backseats of cars are 45% less likely to be injured in a crash than children using a seatbelt alone?

But what is a booster seat, and what’s the difference between that and a car seat? Is there more than one type of booster seat? Which should you buy? Read on to find out the answers to all these questions, and many more besides!

What is a booster seat?

A booster seat is a prop for your child that helps to position the seat belt properly across their chest and pelvis. In the event of a crash, these bony areas will absorb the majority of the impact, minimising the risk of soft tissue injuries.

Why is it important that a seat belt fits children properly?

Seat belts that fit correctly help to protect a child’s hips, sternum, and collar bone in the event of a crash.

Booster seats should also prevent children from slouching, and the shorter seat span stops the lap belt from resting on their bellies, which will keep their organs and spine safer in a collision.

What is the difference between a car seat and a booster seat?

A car seat is a seat that the child sits in. Car seats use three- or five-point harnesses to secure children. By contrast, a booster seat is a seat that a child sits on, secured by the vehicle’s seat belt.

When should you transition your child from a car seat to a booster seat?

Always check the instructions that come with your car seat. These will tell you what the height and weight restrictions are for that specific seat.

Generally, though, your child can be said to have outgrown their car seat when:

  • They have reached or exceeded the maximum weight or height listed for the seat in the product information leaflet/ instructions.
  • Their shoulders are taller than the top harness slots when strapped into the seat.
  • The tops of their ears are in line with the top of the seat.


Types of booster seats

There are two main types of booster seat: high-back and backless.

Both high-back and backless booster seats are designed to make sure your child’s seatbelt fits them properly.

High-back booster seats are the top choice for many parents, especially with smaller children. This is because the sides on the high-back booster help keep seatbelts properly aligned, even when your child is sleeping, and even more crucially, during emergency avoidance maneuvers and heavy breaking.

Backless booster seats tend to be less expensive, and they’re very handy if you’re constantly switching vehicles because they’re less bulky to move around.

However, you should only ever use these in vehicles with built-in head restraints. Plus, you also need to bear in mind that, since 2017, backless booster seats have only been approved for children taller than 125cm who weigh more than 22kg. If your child’s height or weight is below either of these parameters, you must use a high-backed booster seat instead, on the car seat.

Shopping for Booster Seats

There are a lot of different makes out there, which vary in price from >£10.00 to <£200.00, so we’ve

put together a quick list of things to consider when shopping for booster seats which will hopefully make choosing one that little bit simpler!

1. Price isn’t everything. Just because one seat is more expensive than the others, that does not mean it is safer for your child or easier to install.

2. On that note … There isn’t really a “best” or “safest” option; the right choice is the booster seat that

is appropriate for your child’s size, fits well in your car, and is properly installed and used correctly every time the vehicle is in motion.

3. Choose a booster seat that is suitable for the whole time you need it. Children grow fast, so you want to buy a seat that will give your child maximum security and comfort over the course of a couple of years, at least. You can buy adjustable high-backed boosters that allow you to fix the height and width of the seat as your child grows.

As we mentioned, booster seats can be very expensive. That’s another reason you don’t have to buy a new one every time they shoot up an inch! But if the booster seat you think is best is a little bit outside of your budget, don’t worry, you can buy them second-hand. You just need to make sure you know the seat’s history.

Here are our big “don’ts” for purchasing booster seats second-hand:

1. Don’t buy a booster seat that is too old. Look on the label or in the product information to see when the seat was made. More modern seats will be better equipped for safety, and they won’t have as much wear and tear.

2. Do not buy a car or booster seat with missing pieces. Unless the seat is complete, it will not protect your child effectively.

3. If the seller cannot provide you with the product information or installation instructions for the seat, do not buy it. You will not know how to fit it properly otherwise, and booster seats are only effective if they are fitted in the vehicle correctly. Plus, product information is vital so you can know if your child’s seat has been recalled by the manufacturer.

4. Do not buy a second-hand booster seat you know has been recalled. If you are not sure, check with the manufacturer directly before you make your purchase.

5. If there is visible damage to the booster seat, do not buy it.

Installing booster seats in cars

Before installing booster seats, you should always consult the manuals for both the seat and the car, to check that they are compatible.

All booster seats must be used with lap and shoulder belts. If your vehicle only has lap belts in the backseat, you must either look into the possibility of having shoulder belts installed or get a forward-facing car seat with a harness and a big enough height / weight capacity for your child.

When installing your booster seat, follow the instructions carefully. You will know the booster seat is installed properly when the lap belt lies across their upper thighs and the shoulder belt crosses between their chest and shoulder. The seatbelt should never rest on a child’s neck.

The safest place for children under 13 to ride is the backseat, so that is ideally where you should install your child’s booster seat.

The safety element of this is largely to do with airbags, which are installed in the front two seats of all new cars. When used with seatbelts, airbags are very effective at protecting teenagers and adults during crashes. However, they can do a lot of damage to children, especially those riding in rear-facing seats, and to older children who are not properly secured in their car seats or on their boosters.

If your vehicle has an airbag in the passenger seat, you should never place an infant in a rear-facing car seat in that position, unless the airbag has been switched off. This is because the airbag inflating, even in a minor accident, can strike the back of the car seat and cause serious injuries or even death to the child.

Two-seater cars are not ideal for travelling with any children under 13, but if you only have access to a vehicle that does not have a backseat, make sure the front passenger airbag can be and is turned off

before travelling with your child for the first time.

In addition, many new cars also have side airbags. These improve safety for adults involved in side-on collisions. The manual for your vehicle will tell you whether or not you have them and whether or not it is safe to place your child’s car or booster seat next to a side airbag. You should also consult the product information for the seat itself, to make sure that it can withstand the inflation of the side airbag before installing it alongside one.

Should I always replace my child’s booster seat after an accident?

Some manufacturers would say that it depends on the severity of the crash. Certainly, you should replace seats that have been involved in moderate or high-impact crashes, but what are the

guidelines when your vehicle, and the booster seat inside it, have been involved in a minor collision?

Crashes are considered minor when the vehicle can be driven away from the crash-site, the vehicle closest to the booster seat was not damaged, no one in the vehicle was injured, the airbags did not go off, and the booster seat is not broken in any way.

Booster seats that meet all of these criteria are probably still safe to use – but if you are at all unsure,

you should speak to an expert or consider buying a new car seat using our top tips above.

When is it safe for my child to travel without a booster seat?

If your child is 12 years old, or just over 135cm, but you are still unsure as to whether they need a booster seat, check out our tick list below. If you can say yes to all five criteria, it is safe for your child to travel without a booster seat.


1. Their back rests against the back of the seat.


2. Their knees bend over the edge of the seat.


3. The lap belt fits across their thighs, not their belly.


4. The shoulder belt fits across their chest and shoulder, not their neck.


5. You have observed them sitting properly, not slouching or unclipping their seatbelt while the vehicle is in motion.

What else can I do to keep my child safe in the car?

Lead by example, and never leave your child alone in or around cars. Always have your seatbelt on before you start the engine. This will encourage your children to do the same, and hopefully, it will keep them safe for a long time, even when they are old enough to be driving themselves.

It is also important to remember that leaving your child unattended in or around an unlocked vehicle presents many dangers, including risk of injury or death from heatstroke, strangulation, or accidental motion. You should always lock your car when it is not in use to prevent your child from climbing in unsupervised.

What have we learned?

  • There are many different types of car seats. It depends on how old your child is as to which one they need.
  • Booster seats are suitable for school-aged children. The law in the UK requires all children aged 12 and under to travel on a booster seat unless they are taller than 135cm.
  • In turn, there are two different kinds of booster seat. High-backed booster seats are the top choice for many parents.
  • If you are considering buying a backless booster seat, you need to make sure your child is taller than 125cm and weights more than 22kg.
  • Make and model don’t matter as much as size, suitability, and correct installation. ·
  • Booster seats should be installed in the backseat wherever possible. Airbags should be turned off in the front passenger seat where it is not.
  • It is important to replace broken booster seats as soon as possible for maximum safety.
  • Children should not stop travelling in booster seats just because they have turned twelve; if the seatbelt doesn’t fit them correctly over their lap and chest, or if they do not take buckling up very seriously, you should continue to keep them in a booster seat for their own safety.

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