Expiry dates on child car seats - what you need to know

However - and here's the long answer - there are a few differing views on how long car seats can actually be used for. So here we'll tell you what you need to know about car seats and how long they safely last.

1. The life span of a car seat will depend on which Group it falls under

There are currently six Groups in which all car seats fall into:

• Group 0+ - birth to 15 months
• Group 0+/1 - birth up to 18kg (around 4 years)
• Group 1 - 9kg (9 months) to 18kg (around 4 years)
• Group 1/2/3 - 9kg (9 months) to 36kg or 135cm (around 11-12 years)
• Group 2/3 – 18kg (around 7 years) to 36kg or 135cm (around 11-12 years)
• Group 0+/1/2/3 – birth to 36kg or 135cm (around 11-12 years)

While there are some seats that last longer than others, it does not mean that a Group 0+ car seat is safer than a Group 0+/1 because it has a shorter life span. Instead, manufacturers have a recommended service life (see below) for each car seat model.

As long as you are using a car seat that meets the legal safety requirements (more on this below) it can be used continuously as a safe car seat up until your child reaches the maximum weight limit in its Group, when you'll safely move them onto the next stage.

2. Each manufacturer will have a recommended ‘service life’ date for individual products

'Service life' recommendations are a bit like a 'best before' date. They're set by the manufacturers and vary across different car seat models.

For instance, Britax has a 6-year service life for its infant (Group 0+ or Group 1) or harnessed car seats, while Joie has a ‘best before’ date of 5-7 years for its harnessed seats and another 7-10 years for its older child (Group 1, 1/2/3, 2/3 and Group 0+/1/2/3) seats.

So with its new Every Stage seat (a Group 0+/1/2/3, which can be used from birth to 36kg or when your child is around 11-12 years old), if you added the maximum time an infant and booster seat can be used, it would last around 17 years.

The service life also depends on how you use the car seat.

If you used an all-stage car seat for one child and kept it in the car while your little one grew through all the groups as anticipated, it will last beyond the full 12 years, and you won't have to change it.

However, if you were a child minder who used the seat for carrying children below 4 years then best practice, according to Joie, would be to change the seat every 5 to 7 years as you would only ever use it in the Group 0+ or Group 1 mode.

But always check with the car seat manufacturer if in any doubt.

3. Car seats must be safety tested and certified

All car seats must show an ECE approval sticker (see example above) to show that the seat has been tested and complies with the basic safety legal requirements. The sticker will also show you what Group the seat is tested for and the maximum weight it can be used up to.

There are currently only three legal regulations (ECE R44.03 ECE R44.04 or ECE R129) that can be used on the road today in Europe. It’s worth noting that the R44.03 was introduced in 1995 and is over two decades old.

The R129 law came into force in 2015 and has been designed to make it safer for children when travelling in a car by using new smarter crash test dummies, promoting ISOFIX and by making little ones sit rear-facing for longer.

4. Plastics degrade over time

Plastics do degrade over time and so may not perform as initially designed. And it’s due to this that car seats have ‘service life’ recommendations.

Also, car seat laws change quite often, as there are continual advances in new safety technology, which is why it’s a good idea to upgrade to a newer car seat.

It's worth knowing there is no legal obligation for a car seat not to be used beyond any specific time period - unless the laws change. We'll certainly make sure you hear about it if it does!

5. Don’t buy second hand car seats

Safety experts recommend that you avoid secondhand car seats altogether. You can never be totally sure that it hasn’t been involved in an accident, even when buying from family or friends.

It’s not that you'd be intentionally misled, just that some bumps and crunches can be forgotten easily enough, but still affect the car seat.

Are you after more car seat information? Then check these out...

• What is i-Size for car seats?
• Guide to child car seat laws and safety
• 12 of the best car seats from 9 months