Buying a Car Seat


Choosing the right car seat for children can be a frustrating and confusing process, with different regulations, terminology and many, many products to choose from. But it needn't be like that so let the Safely Travelled buying guide help you navigate the complexity so that you can identify the very best car seat for you and your child. 

This guide is split in to five steps to help you find what works for you:

1. The Law
2. Your child's needs
3. Installation and Your Car
4. Choosing what works for you
5. Summary

With two further optional areas:

6. Understanding Car Seat Regulations
7. Further Questions and Jargon Buster


1. The Law or Why do I need a Children's Car Seat
The first step to choosing a car seat is to understand the law. Thankfully the law in the UK is very clearly stated; if your child is travelling in a car or a van, then they must be in a children's car seat. The only exceptions are:

- When your child is either 135cm in height or over the age of 12, whichever comes first.

- When you are travelling in a registered taxi or mini-cab, but they must sit in the back and, if over the age of 3, use a seat belt.

In simple terms this means you must have a car seat when carrying children in our own cars and obviously, as parents we all want to do our very best to ensure our children are safe from harm. 


2. Your Child's Needs
The second step to choosing a car seat is identifying the type of car seat that is right for your child's size. There are two "systems" in place for this one of which is weight based, called R44 regulation seats (Group 0, 1 etc.) and one of which is height based, called R129 but known as iSize. Not to be confused with ISOFIX, which is covered in the next section. The size classifications for these two regulations are covered in detail in Section 5 but it results in four types of car seat:

Carry Cot - For use from birth through to 6 months old, these are designed for you baby to lie flat while in the car. As a result they are often called lie flat car seats and typically are placed side on to the direction of travel. 

Infant Carrier - Also for use from birth, these are rear facing and have your baby in reclined, but not flat, position. They are designed so that they can be easily removed from the car and therefore are often intended to be used with a base unit, that remains in the car. In addition they can also fix on to the base of a pram/buggy for seamless transition from car to outside. 

Toddler - These seats are the next stage on from the Infant Carrier, with transition typically happening after 18months, although some are designed to carry children from birth. Some are forward facing only, some are rear facing and in the case of some can do both, and which orientation you choose is dependent on weight or height. 

Child - These are the final type of seats and are designed for children who have outgrown their Toddler seat. They are designed to lift the child up such that they can use the car seat belts and are often referred to as booster seats. Your child will stay in this seat until they are either 12 years old or 135cm, whichever comes first. 

It is not always necessary to have a seat from each of the four categories above as there are seats that span more than one child size. There are some popular well trodden paths that reduce the number of seats that you may wish to follow:

- One Seat: Baby, Toddler & Child Seat (3 in 1 combined)

- Two Seats: Baby & Toddler Seat > Toddler and Child Seat (2 in 1 combined)

- Three Seats: Baby Seat > Toddler Seat > Child Seat


3. Installation and Your Car
By now you've identified the kind of car seat that is right for your child's life stage and the next step is to understand what installation options you have in your car and how much space you have available.

For the purpose of fitting car seats you need identify which of these three installation options you have:

- Your car does not have ISOFIX

- Your car has ISOFIX but no Top Tether mounting

- Your car has ISOFIX and a Top Tether mounting

What is ISOFIX?
ISOFIX is an international standard with respect to fittings seats in cars, but what it means in practice is that a car fitted with it will have dedicated anchorage points built in to the back seats. In the early days of ISOFIX manufacturers hid these mounting points in the join between the rear seat base and the rear seat back. More recently they have become much more conspicuous, often behind plastic caps and with small logos sewn in to the seat cloth. 

ISOFIX Mercedes W204

What is Top Tether?
Top Tether is the name given to a car seat mounting point that exists as part of the ISOFIX system. It takes the form of a web strap (just like a seat belt) that extends from the rear of the seat and clips on to a dedicated mounting point. On some cars this mounting point is on the rear face of the back seat (hatchbacks, estates and SUVs) or at the rear of the boot space. On saloon cars this mounting point is more likely found on the rear shelf. Any car built since February 2013 will have a top tether point, but it is not always required. However if the car seat you buy has top tether fixing then you must use it. 

Does my car have ISOFIX?
This is a good question and it's not always an easy one to answer. Since 2013 ever car built for the EU market has had to have ISOFIX and a top tether point so if your car is newer than this it will have it. Do remember that this is the build date, not the sold date however. However if your car is older, it may not have it.

ISOFIX was first introduced in 1997 and from the early 00s a lot of cars had it fitted, but not all. Personally I've owned an Audi built in 2002 that has ISOFIX and another Audi built in 2003 that didn't have it. Similarly I've had a car from 2005 that didn't have it, but ISOFIX was an option so another 2005 car of the same model could have it if the original owner had chosen it.

You could ask your manufacturer or consult your handbook but the definitive way to tell is to check yourself as well as looking for the labels.

ISOFIX Fiat Bravo 198

Can I retrofit ISOFIX?
The short answer is to assume that no, you can't. But the long answer is that, yes, you can, but it depends on the car in question. See the "Further Questions and Jargon Buster" section below for more information.

What Does This All Mean?
Car seat installation can seem like a minefield, but breaking it down it works out like this.

Your Car Doesn't Have ISOFIX  - In this scenario you will need to buy a car seat that attaches to the car using the car's seat belts. This isn't any less safe than ISOFIX, afterall a car seat belt is designed to restrain the weight of an adult, but there is a greater risk of mis-installation by not routing the belt correctly or it not being tight. 

You Car Has ISOFIX but not Top Tether - In this scenario you can either buy a seat that uses the car's seat belts or and ISOFIX seat that doesn't use top tether. Typically those seats are the ones with a support leg.  

Your Car Has ISOFIX and Top Tether  - In this scenario you can buy any seat that fits in the space available with the optimum being an ISOFIX seat. 


4. Choosing What Works For You
The final step in choosing a car seat is ensuring that you buy one that not only suits your child and your car but also your own needs.

Consider the Size
Car seats are bulky, extended rear facing (ERF) models especially so. So while an ERF seat may be right for your child and technically compatible with your car's ISOFIX configuration it might not actually fit. This is particularly a challenge with smaller cars, which often have smaller rear passenger compartments. As an example this below is a Maxi Cosi 2way Pearl in a Mercedes E-Class with the driver's seat configured for average height and it only just fits. 

Maxi Cosi 2way Pearl Mercedes W213

Consider Day to Day Use
Car seat manufacturers work hard to ensure that their products are easy to use, but there are certain things to look for that can really help in day to day life. For example recently manufacturers have introduced more swivel seats and these really do help as they enable you to lift you child in and out in a straight line, rather than at an angle. But they are typically more expensive than those that don't rotate.

Similarly if you are planning to move your car seat between cars then you should consider models that are either light or clip in to a base rather than those that are intended to be fitted and left.

Consider Spares and Manufacturer Support
Car seats are, by their very nature, robust but things do wear out or break and it's here where you want to ensure there is good manufacturer support. Can you get spare parts easily and quickly? Can you purchase spare seat covers in the event that you can't get the current one clean?

Consider Your Child's Comfort
It sounds obvious, but put your child in some seats and see if they look comfortable (or ask them, if they are old enough). Nobody wants to sit a seat that isn't comfortable as an adult, and neither should a child. So look at the fabric, feel the padding and check the lay of the straps to ensure your child can be as comfortable as possible. 


5. Summary
In summary choosing a car seat is about following a process to short list a number of models and then within that subset choosing the one that works best for you as a family. Laid out that looks like this:

1. Ensure you are complying with the law

2. Identify the type of car seat appropriate for your child's life stage (e.g. Toddler)

3. From that type of car seat, identify those that are compatible with your car's installation options (e.g. ISOFIX)

4. From that short list select those that fit in your car with your front seats at a normal position. And from those, choose the one with the features you most desire from a reputable manufacturer.

Here at Safely Travelled we are always happy to discuss your options so if you are struggling to navigate the decision process do give us a call and we can talk you through it. 


6. Understanding the Regulations
There are two sets of regulation that currently run along side each other, R44/)4 and R129, also known as i-Size.

R44/04. This is a weight based standard and classification are given as Group 0, Group 1 and so on. This standard is on its fourth iteration, hence R44/04 and the previous iteration is R44/03. It is now illegal to sell a new car seat that only meets iteration #03 but it is still legal to use one. 

R129. This is height based standard and is newer than R44/04. The testing regime is stricter with greater attention paid to side impact testing. It is also known as iSize so if you see and R129 seat it will be an iSize seat. As a result it will also have ISOFIX, since that is a mandatory requirements of R129 approval. 

What does this mean in practice?
The two regulations currently run side by side. It was intended that R129 would replace R44/04 but that hasn't happened yet. As a result there are products on the market that comply with one standard and those that comply with the other. 

If you are looking for a seat that is retained by your car's seat belts only (because you don't have ISOFIX for example) then R129 is less relevant for you, as that regulation only applies to ISOFIX compatible car seats. 

If you are shopping for an ISOFIX seat then you can look at products that comply with either regulation. 


7. Further Questions and Jargon Buster

Why are there no seats with harnesses above 18kg?
Once a child gets above 18kg it is safer for them to be restrained by the car's integral seat belts. To continue to restrain a child over 18kg using the harnesses built in to the car seat would require a significant amount of reinforcement which would lead to the car seat being more bulky and with the car's seat belts being ready and available, it isn't necessary.

What about 2nd hand car seats
It is often said that you shouldn't buy a 2nd hand car seat because you won't know if it's been in an accident and/or has suffered such that it is no longer as strong as it should be. 

This makes sense and certainly buying from a total stranger is potentially very risky. However a used car seat where you know nothing has happened to it (e.g. from a family member) makes sound economic and environmental sense. Obviously you will need to check it thoroughly before use to ensure that nothing has been compromised but if they were happy to carry their children in it you should be comfortable to do the same. 

When does a car seat reach the end of its life?
Common advice is that car seats should not be used beyond 10 years after their point of manufacture. Thankfully all car seats have their date of manufacture on them, either through a standard date stamp in the plastic or via the orange certification label. 

The logic here is that beyond 10 years the strength of the plastic and other materials cannot be guaranteed and while they might still be strong enough, it isn't worth the risk

What about car seats on the front seat?
This is legal but it is essential that you deactivate the front passenger airbag. If you can't do this, then you must not install a car seat on the front passenger seat. Also be aware that some cars have ISOFIX on the front seat (Renaults, Audis) and some do not. Some manufacturers sell seats that automatically deactivate the front seat airbag (Mercedes) but you can't deactivate that airbag with any other seat. 

How to tell if you car has ISOFIX?
The simplest way to tell if you car has ISOFX is to check yourself. In more recent cars there will be small tabs sewn in to the seat where the brackets are. In older cars these aren't there, so it's a case of sliding your hand in between the seat base and the seat back and feeling for them. They are always in the same place, irrespective of the car, so if they are there you will quickly find them. 

Can I retrofit ISOFIX?
Yes you can, if you make and model of car supports it. Here's a a direct example from the Safely Travelled household

"My Mercedes C-Class was built in 2005 and at the time ISOFIX was an option in the price list, but it hadn't been fitted to my car. However it did have all the necessary mounting points to allow for ISOFIX brackets to be fitted. I therefore ordered the brackets from my local Mercedes dealer and fitted them myself using a socket set and a torque wrench."

ISOFIX Retrofit Kit Mercedes W203

Some dealers are very reluctant to sell you the parts however for fear that you will get it wrong, which is understandable. But if you are confident in using a socket set and a torque wrench you will be able to retrofit ISOFIX, assuming a kit is available. As well as Mercedes, ISOFIX retrofit kits are available from Audi and Ford.

ISOFIX Retrofit Mercedes W203 Installation
ISOFIX Retrofit Mercedes W203 Installed

For some cars though, the ISOFIX brackets are not bolted down but are welded on at point of manufacture. In that scenario retrofitting ISOFIX is impossible. 


Jargon Buster

The world of children's car seats is full of terms that aren't used anywhere else. Here we've deciphered the most common ones. 

ISOFIX - The international standard for attachment points for child safety seats in passenger cars. It is made up of two parts, the ISOFIX attachment in the car and the ISOFIX compatible clips built in to the car seat or seat base. 

I-Size - Also known as Regulation R129, i-Size is a car seat legislation which launched in 2013. All i-Size seats have ISOFIX mounts. 

Top Tether - This is the mechanism for securing an ISOFIX car seat (but not base) through use of a webbed belt attaching to an anchor point in the car, often found on the rear of the back seat or along the back of boot. 

Foot Prop - This is a supporting foot that keeps an ISOFIX car seat stable if it isn't secured by a top tether. They adjust for height to accommodate different cars.