Knowledge of child car seats is essential for any parent or guardian. They’re a safety requirement for newborns and children up to 11 years old, or those of a certain height. Yet many underestimate the risks and penalties of breaking this law.

Our guide addresses car seat rules and common misconceptions in the UK, providing a one-stop-shop for all parents looking for more information.

Introduction to child car seats

Guaranteeing the safety of your loved ones should always be the priority. That’s why it’s crucial to understand every aspect of using a child car seat.

These devices have been a focus of road safety legislation in recent years, and since their introduction in 1962, they have saved countless lives.

Why do we need child car seats?

A lot of time, money and effort is spent on making cars as safe as they can be, with regular tests carried out to ensure they’re roadworthy.

But that doesn’t make child safety seats any less important, especially when you consider they have to be designed to match the developing dimensions of babies and children.

  • Children (especially babies) have different proportions – with smaller limbs in relation to head size.
  • Babies have their major organs located in different places.
  • Children have unformed muscles and bones.
  • Young children and babies have a higher vulnerability to injury.

A recent study by Safeseats4kids showed child safety increased up to 82% when a child car seat was used – with a 28% lower risk of death compared to regular seatbelts.

For this reason, child car seats are integral to the safety of kids across the country. Without these devices, millions of children would be put in danger on a daily basis.

What is the law on car seats in the UK?

As of right now, the UK government deems a car seat must be used if:

  • A child is 11 years old or younger
  • A child is shorter than 135cm in height

Although some of the requirements are fairly easy to follow, the laws on child car seats in the UK are more complex than you might imagine. Once you get past the basics, child seats fall into two categories:

  1. Height-based seats

    These are also known as ”i-Size” seats and should be rear-facing in your car (pointing in the opposite direction of travel) until your child is older than 15 months. Naturally, you should check to see if the size of this device is right for the height of your child.

    The basic design provides better protection against collisions with side impact. This EU innovation was introduced after a Swedish study found young children using these were 75%% safer than those in front-facing seats.

    To make sure the seat you’re using is compliant with regulations, it should have a capital ’E’ (Europe) in a circle, as well as a label reading ’R129’.

  2. Weight-based seats

    Unlike the one-size-fits-all approach of i-Size seats, weight-based models vary depending on your child. These fall into five separate categories:

    • Group 0 (0kg to 10kg) – Lateral baby carrier and rear-facing baby carrier
    • Group 0+ (0kg-13kg) – Rear-facing baby carrier and rear-facing baby seat using harness
    • Group 1 (9kg-18kg) – Rear or forward-facing baby seat using harness or safety shield
    • Group 2 (15kg-25kg) – Rear or forward-facing child seat using seatbelt, harness or safety shield
    • Group 3 (22kg-36kg) – Rear or forward-facing child car seat using a seatbelt, harness or safety shield

    Much like height-based seats, these are recognisable by labels. They’ll also have a capital ’E’, as well as an ’ECE R44’ label.

    If you’re caught driving in a car where a child is not properly secured, you’ll receive a £100 fixed penalty notice on the spot. If the matter goes to court, it could cost you as much as £500.

Car seat exemptions

Just as with any law, there are always exceptions to the rule. These will differ depending on the age of the child in question.

Under three years old

There is only one exception to the law when it comes to children under three. This is when they travel in the backseat of a taxi or privately hired car, where there is no appropriate seat available. In this instance, it falls on the driver of the car to ensure the child is restrained.

Aged over three years old (until 12 or taller than 135cm)

Things are a little different for children who are in an older age and size bracket. In this instance, there are four exceptions:

  1. In the back seat of a taxi or privately hired car
  2. On a short-distance journey which is unexpected or sudden
  3. When there are already two child restraints in the rear, so a third can’t be fitted
  4. If the car has not been manufactured with seatbelts

If any of these apply, you’ll be able to transport a child without being fined for not properly securing them. But the responsibility will again fall on the driver to ensure the child is safe.

Children with disabilities or medical conditions

All medical conditions must be given extra care and attention. But it’s particularly important in the case of children with hip dysplasia.

Hip dysplasia is said to affect 1-3% of newborns. Babies will need a cast once the condition has been diagnosed, so parents often find a regular car seat is not suitable.

As such, specialist devices have been built to accommodate for babies with the condition. These help provide a comfortable ride for them, and reduces the risk of long-lasting hip problems.

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The different types of child seats

As well as height and weight-based car seats, you’ll come across some other key differences when comparing the different types.

Rear-facing child car seats

Rear-facing seats have become incredibly popular in recent years. In fact, most medical professionals now recommend them:

A rear-facing child safety seat does a better job of supporting the head, neck and spine of infants and toddlers in a crash, because it distributes the force of the collision over the entire body. Denis Durbin, Co-scientific director of the Center for Injury Research and Prevention at The Children’s Hospital of Philadelphia

If there’s an accident on the road, rear-facing seats will offer a baby or young child protection in four unique ways:

  • It prevents the child’s head moving around, which reduces the chance of neck injury
  • It stops the head hitting hard surfaces after impact
  • Pressure is distributed all over the body
  • A protective shell stops shattered glass harming the infant

Aside from these important safety factors, there are also a number of other benefits for using this type of seat.

For one thing, they offer great value for any parent. The nature of adjustable rear-facing seats means your child should be able to make use of them until they’re around four years old.

You’ll also be able to have a seat specially measured for your car. However, this is likely to be expensive. Which? suggest parents can expect to pay anywhere between £300-£350 for custom-made seats.

Front-facing child car seats

Front-facing child car seats are what we’ve come to recognise as the norm in most cars. The law says children must use these until they’re either 135cm tall or 12 years old.

If you’re a parent worrying about which seat is appropriate for your little one, it might be worth bearing some of the following tips in mind:

  • Some forward-facing seats have harnesses to hold a child in place. Once they reach a certain age or height, you can switch to a seatbelt.
  • While hand-me-downs might seem useful, you’ll want to make sure the seat you’re given meets all safety standards. Also, remember to never buy a second-hand car seat from someone you don’t know. This is explained in more detail further on.
  • Once fitted, use the inch test. If you can move the seat more than an inch when you pull, it’s not installed correctly.
  • Use the pinch test. Try to pinch the strap at your child’s shoulders. If you can grab excess webbing, it needs to be tightened.
  • Think about bundles that include both a car seat and a pushchair. This might reduce the overall price of the seat.

A handy addition is an impact cushion attached to the front, absorbing some of the impact of a collision. It’s suggested a child should stay in this type of seat until they’ve outgrown it.

Booster seats

Booster seats are effectively one step up from a regular child car seat, but aimed at slightly older children. From February 2017, manufacturers have been restricted from producing backless versions of these seats.

Interestingly, there is no legal requirement for parents with a backless seat to update their current model for a new one. But, how do you know if you need a booster seat in the first place?

If you answer ’yes’ to any of these questions, it’s time to get one&hellipsis;

  1. Does your child exceed the height or weight limits of their current seat?
  2. Are the shoulders of your child above the slot of the harness?
  3. Are the tops of your child’s ears above the car seat?

As with any of the seats we’ve spoken about, it’s important to make sure you buy a make or model that has been fully tested and fits the size of your child.

What is Isofix?

Isofix is an innovative system with additional ports added to your car. This means it’s much easier to fit a child seat without sacrificing on safety – great news for busy parents.

Every car built after 2011 includes Isofix. Just check with your car manufacturer or manual if you’re unsure whether you have this additional safety feature in your car. You can also check for staple-shaped fittings between the back and bottom of the seat.

Aside from improving safety, Isofix also provide children with a leg support system. This also stops seats from tipping forward in a crash. They’re adjustable, and should be altered according to your child’s size.

As with any seat, you should make sure the one you’ve bought fits in the back of your car without any struggle.

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Guide to choosing & fitting a car seat

It’s not as simple as choosing a seat and dropping it in the back of your car. You need to decide what will match the needs of your child, as well as how to best fit the device safely.

What is the best car seat for a newborn?

The best car seats for newborn babies often fall into the 0+ category. This range is targeted at newborns to those weighing up to 13kg.

In 2017, Madeformums carried out a survey focusing on the best seats for babies. Here’s what they found to be among the top models:

  1. Cybex Cloud Q - This seat comes with either a three-point belt or Isofix base, depending on how much you want to pay. With an adjustable headrest and side-impact cushioning technology, its lie-flat function makes journeys as comfortable as possible for little ones, while providing protection.
  2. Britax Baby SAFE – You’re in good company with this one, as Prince William has purchased two after the birth of his children. Isofix adaptors and increased head and neck protection make it a fantastic option for any guardians concerned with safety.
  3. Jane Matrix Lie-flat - This option makes sense for parents, thanks to its versatility. The Jane Matrix doubles up as a carrycot on pushchairs, and is even safe for overnight sleeping. Four recline positions complete the multipurpose use of this handy infant seat.
  4. Kiddy Evo-luna - A five-point safety harness, rocker function and travel compatibility system make this one of the more appealing and safe seats on the current market. If you’re regularly heading off on long journeys, this could be a perfect option for you.

What is the best car seat for a toddler?

Once again, Madeformums carried out the survey - only this time with the parents of toddlers taken into account. The results highlighted four more top seats worth trying:

  1. Graco Nautilus Elite – This is long-lasting, and has a five-position headrest, with side impact protection to ensure there are no mishaps. To add a finishing touch, the seat even comes with a cup holder. Safety and convenience all in one.
  2. Cosatto Hug Isofix – This colourful device is popular for not only its vibrant design, but also the fact it’s fitted with a harness preventing kids from wriggling free. A six-position headrest and Isofix tech add to the appeal, and guarantee a safe journey from start to finish.
  3. Multimac – If you have to care for two or more toddlers, the Multimac could be the best option for you. Up to four kids can fit in, with a tether strap system able to separate the seats – allowing adults to sit in the back when needs be.
  4. Maxi-Cosi 2way Pearl – The Maxi Cosi is popular with most parents, largely because it offers both rear and forward-facing options to infants. A recline function which is easy to use, and an excellent durability factor makes it exceptionally safe.

As your child is now a little older – more than likely at an age where they can make their own decisions – let them have a say in which seat feels most comfortable.

Buying a car seat

Once you know what kind of car seat you’re after, the next thing is finding the right place to buy it from. It’s important to get this right, to ensure the safety of your child.

Buying second-hand

It’s not advised to buy a child seat that has already been used. You may be able to save money, but it isn’t worth putting your child’s safety at risk. There are several reasons why choosing to buy a second hand car seat is a bad idea:

  • Damage. Seats are specially designed to cushion and protect your infant’s head, neck and body. If there’s even the slightest compromise to the plastic or metal, it’s less effective. This isn’t always easy to spot, as most damage won’t be superficial. Rather it’ll be to the main body of the seat itself, underneath layers of fabric.
  • The unknown. When purchasing second-hand, it’s unlikely you’ll know about the exact history of the seat itself. It may have been involved in a crash in the past. According to Made For Mums, a collision of 30mph is enough to damage a seat to the extent that it shouldn’t be used again.
  • Expiration. That’s right; car seats can actually expire. Plastic becomes brittle and more prone to breaking with age. Most seats will expire within six years of construction, while others can last 10 years depending on the material. So although there’s a shelf life for most car seats, it can sometimes be impossible to know if your seat is even in date.
  • A lack of instruction. It’s important to know how to correctly install your seat to ensure the highest levels of safety. There’s a good chance you won’t have access to these instructions if you buy a seat second-hand. Failing to fit properly could prove deadly.
  • Missing parts. • If a seat hasn’t been cared for properly, it may be missing some parts. This includes straps or buckles that aren’t immediately noticeable.

If you do decide to buy a car seat second-hand, make sure you always:

  • Ensure manufacturer instructions are included
  • Visually assess it for damage (thoroughly)
  • Make sure the seat is perfect for your child’s weight and height
  • Look for the ”E” label to prove it meets the United Nations’ standard regulations

However, there’s no cheap alternative when it comes to dealing with the lives of your loved ones. Therefore, it’s highly recommended that you purchase a brand new seat for your child.

Where to buy

There are several reliable outlets that sell child car seats. This actually makes finding the right one a challenge. Here are some of the most common places to buy a seat.

Online retailers

  • Examples: Argos, Amazon and eBay
  • Benefits: Seats can be bought at the click of a button. You can read a lengthy list of online reviews to find something that is reliable, as well as a detailed product listing. In some instances, you’ll even find a high street chain’s online store, saving you the time of travelling there yourself.
  • Risks: You never see the seat before you buy. You aren’t dealing with another person (face-to-face) at any point in the buying journey. Products might be damaged in transit but not show any signs of mishandling.


  • Examples: Tesco, ASDA and Aldi
  • Benefits: These seats come from a recognisable and respected name, perhaps where you do your weekly shop. Supermarkets often offer good value for money. You can discuss your options with a worker in store. You can inspect the seat for yourself.
  • Risks: There may not be anyone with specialist knowledge of the seat (or child seats in general) on hand.

Chain stores

  • Examples: Babies R Us, Mothercare and Halfords
  • Benefits: These stores offer specialist knowledge you’re unlikely to find elsewhere. You can test and assess the seats in store. Staff will fit the seat in your car as part of an optional service. You have peace of mind knowing this is what these companies specialise in.
  • Risks: Some installation processes have been found to be inadequate in the past.

With this in mind, it falls on you to decide where you want to buy seat. Each outlet has pros and cons, so it all comes down to your preference.

Top tips for picking the right car seat

With such a wide range of makes and models available, picking a child seat can be as hard as choosing a car.

To make things that little bit easier for you, consider some of the following tips:

  1. Think about your child

    Firstly, and most importantly, you’ll want to take the size of your little one into account. We’ve already explored how different weights and heights place them in categories. Age will also be a contributing factor.

    Generally speaking, this quick guide should help:

    • Birth to two years old – Rear-facing child car seats are best for this age group. Their weight should not exceed the seat’s recommended limit.
    • 2-4 years old (and 40+ pounds) - A forward-facing car seat is the best option.
    • 4-11 years old (or 4ft 9 inches and below) - Use a backless booster seat.
    • 12+ - Regular adult seatbelts can be used from this point onwards, so long as your child fits into them properly (if they’re above 135cm). If they don’t, they must remain in a booster.

    These are just recommended age ranges. It’s important to take their size and weight into account before you make any purchase.

  2. Check the safety levels of the seat

    Make sure you do a thorough safety check when it comes to how fit-for-use the seat actually is. Look out for the safety labels - these will be the large ”E” and ”R129” or ”ECE R44” codes.

    If you’re getting your seat from a store, you should ask the staff if they’re IOSH (Institution of Occupational Safety and Health) approved. If they’ve got an accredited number, you can trust them.

  3. Make sure there’s enough room in the back

    You should have room for a seat in your car – but you also need to take other factors into account. How many people often travel in the back? Do you need more than one seat? These are just some of the questions you need to bear in mind.

  4. Find out if your car can hold a child seat

    It’s also important to check to see if your car is actually able to support the addition of a child seat. As well as this, decide what kind of device you want to attach the seat with. This will be either a belt or LATCH (Lower Anchors and Tethers for Children) system. Remember, some Isofix seats might be too advanced for older cars.

How to correctly fit a car seat

Once you know the seat you want, the next step is accurately and safely fitting it to your car. This will vary depending on what you’re fitting the seat with:

Isofix & i-Size

Not all cars are designed to fit an Isofix seat. There will need to be a connector in the joint between the back of the seat and the cushion.

For Isofix seats:

  • Check that your Isofix seat is approved for use in your particular vehicle. Isofix seats will not fit in every car with Isofix points.
  • As with any child car seat, follow the manufacturer's instructions carefully.
  • Isofix cars have Isofix slots hidden behind the car's rear seats - in the joint between the back of the seat and the seat cushion. Some cars have a third Isofix attachment point, for a top tether, behind the rear seat to stop the child seat tipping forward in an accident.
  • Locate the Isofix points in your car by checking your car's handbook and looking for the Isofix label on the rear seats.
  • Locate the Isofix connectors (two prongs sticking out of the back) on the child seat or base.
  • Push the connectors into the Isofix slots in the car seat. There will be an audible click on many child seats, and/or a visible indicator that turns from red to green, to show that the child seat has been securely attached.
  • If using the top tether fixing point, connect the top tether strap to the top tether point in the car. Do not attach it to anything else, such as a head restraint or luggage hook as they will not be strong enough.
  • If using a child seat with a supporting leg, do make sure the leg is correctly adjusted so the seat is braced against the floor. Some have a visible indicator that turns green when they’re set correctly. Make sure the leg is not sitting over an underfloor storage compartment because this may collapse from the force of an impact coming through the support foot.

In the case of i-Size seats, the same process applies. There are fewer cars with the right fittings for these though, so you might be hard-pressed to find one. If you’re thinking of using an i-Size seat, make sure you check your car before buying.

Regular seatbelts

When fitting a seat using a regular seatbelt, there are steps that should be followed:

  • Attach the seatbelt with the blue guides in a rear-facing seat, and with the red ones in a forward-facing seat.
  • Push all your weight into the seat to securely hold it in place.
  • Ensure there’s no slack when you pull on the belt.
  • Place the locking device in position and click shut.
  • Make sure the belt buckle is not resting on the child seat frame.

Mistakes to avoid

We’ve already touched on some of them, but there are mistakes you’ll want to avoid when properly fitting a seat:

  • A slack harness – Always make sure this is as tight as can be. You shouldn’t be able to fit two fingers between the harness and the seat.
  • Guessing – Most seats will be fitted as per the instructions above, but always read the manual instructions carefully in case yours is different.
  • Strap them in – Remember to not only secure the child seat, but also click the seatbelt into place. Surprisingly, many people overlook this.
  • Keep the buckle off the frame – Make sure the buckle isn’t resting on the child seat frame – known as buckle crunch.

So long as you steer clear of these mistakes, you should be able to ensure your child is safe and ready for a car journey.

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Updated on 13/07/2017