The Good Egg Car Safety Blog

Child seat group stages

For child car seats to legally be sold in the UK, they must pass various tests and gain recognised approval. To be sold, they can be approved to R44.04, which is a regulation that has been running for some years, or they can be tested under the new R129 (i-Size) standard, which was established in summer 2013.

This blog looks at the different group stages for R44.04 child car seats, along with the weight and the height limits that you should take into consideration. There are three main group stages and also combination group stages to create multi stage, longer lasting seats.

Group 0+

The infant car seat is normally the first car seat you use for your baby. It is suitable from newborn and has extra padding to keep little one's safe and comfortable. These seats fit your baby until 13kg in weight is reached, or until the top of their head is level with the top of the seat.

It is not dangerous for your baby's legs to hang over the end of the seat, and it is not unsafe if their feet are touching the vehicle seat back.

Group 1

After your baby has outgrown the infant seat, many parents choose to move their baby into a group 1 car seat. Group 1 car seats are approved for young children weighing 9-18kg, and they become outgrown when little one reaches 18kg in weight, or when their eyes are level with the top of the car seat.

Although group 1 car seats are approved from 9kg, your little one is far safer rear facing in their group 0+ infant carrier as long as possible. We recommend that you use the infant seat (group 0+) until it is fully outgrown. If your little one has outgrown their infant seat by height, a group 0+1 combination car seat can allow you to carry on the extra safety of rear facing for a while longer.

Group 2, 3

Now your little one is growing and getting older, they can move up into a high back booster. This is a child car seat with deeply padded head and side wings, and your child is restrained with the adult seat belt. These seats are approved for children weighing 15kg – 36kg, and UK law requires children to be in these seats until they are 135cm in height, or 12 years of age – whichever comes sooner. Many high back boosters will accommodate taller children.

As with moving from the infant seat to a group 1 car seat, your child is safest using the 5 point harness for as long as possible. They should only move into a high back booster provided they weigh a minimum of 15kg and have outgrown their group 1 car seat. If your child is below 18kg, a group 123 car seat can allow you to continue using the harness for a while longer. For children who still need a harness over 18kg, please read the sections on group 1,2 and 1,2,3.

Combination Stages

The above group stages are the main group stages for child seats, however, you can have combinations of the stages to create multi stage or longer lasting seats. The most popular multi stage seats are detailed below.

Group 0+1

Group 0+1 car seats are approved from birth – 18kg. They often have additional protective and comfort inserts for newborns, and they are approved to be in group 0+ stage rear facing up to 13kg. When used in group 1 mode, some seats allow you to carry on rear facing right up to 18kg, whereas others are approved forward facing 9-18kg, so you must turn your baby forward once they reach the rear facing weight limit.

Considering how long you would like your baby rear facing is important to take into consideration when buying a group 0+1 car seat.

These seats are outgrown when the maximum weight limit is reached, or when little one's eyes are level with the top of the car seat shell.

Group 1,2

Group 1, 2 car seats have traditionally been very popular in Scandinavian countries, where children are generally kept rear facing until they are 4-6 years old. They are becoming increasingly popular in the UK, and they offer the ability to continue using the 5 point harness beyond 18kg, right up to 25kg.

These seats tend to be rear facing in the car, and are fitted with the vehicle seat belt and tether straps – many seats also have a support leg. The harness can be used for children weighing 9-25kg, and the seat is outgrown when the weight limit is reached, or when the child's eyes are level with the top of the car seat.

They are particularly useful for parents who want to rear face for as long as possible – beyond 4 years old, and also for higher percentile children who are likely to out grown an 18kg harness long before they reach 4 years of age.

Group 1,2,3

Group 123 car seats combine the group 1 harness, with a high back booster. Children can use the harness between 9-18kg, and the seat then converts to a high back booster, until they no longer need a seat. These combination seats tend to be a belted installation, although there are some ISOFIX options available.

The 5 point harness can be used right up to 18kg, or until your child's eyes are level with the top of the car seat shell. At this stage, the harness is removed from the seat, and your child is restrained with the adult 3 point seat belt. The booster headrest can be adjusted to accommodate your growing child, up to 135cm in height or 12 years old, whichever comes first.

Some group 123 car seats are now introducing 25kg harness weight limits, such as the Britax Advansafix, which is great news for parents who want their little one to use a harness if they're over 18kg. This is a seat which uses ISOFIX and a Top Tether, plus the adult seat belt, for a very secure installation.

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