R129 (i-Size) and R44/04 Car Seat Regulations
By law all children must travel in the car in a seat that is suitable for their weight, height and age.
There are two car seat regulations in Europe, ECE R129 which was introduced in 2013 and ECE R44 which has been around since the early 1980s (the current version is R44/04). R44 was discontinued in September 2023 and although you can continue to use any R44/04 seats that you already own, most manufacturers have now stopped making them.
There are a few differences between R129 and R44/04 car seats
- In an R129 car seat all children must rear face until they are at least 15 months old or 76cm tall, regardless of their weight. R44/04 allows forward facing from 9kg regardless of age.
- R129 car seats have height limits, they don't have set weight groups like R44/04 ones do.
- Advanced technology 'Q' crash test dummies have 32 sensors to simulate a child’s fragile body more accurately. The 'P' dummies used for R44/04 only have 4 sensors.
- R129 car seats have all passed a side-impact test which is not compulsory in R44/04 testing.
- I-Size child seats are guaranteed to fit in any i-Size approved vehicle. From 2016 onwards some, but not all, new cars have at least two i-Size compatible seats.
- R129 can seats can be no more than 44cm wide to increase the chance of being able to fit three seats across the back seat of the car. R44/04 seats have no width restrictions and can be as wide as 48cm.
- In most R44/04 combination seats the belt is routed differently for rear and forward facing. R129 seats only have one belt path for both travel directions, to avoid confusion and prevent mistakes.
- Belt fitted R44/04 seats have blue seat belt guides for rear facing seats, and red for forward facing. In R129 seats all belt guides are green.
R129 car seats for older children come in four height categories
- i-Size Infant carriers up to around 75-85cm (these limits vary, so please check your instruction manual to check your seat's limit)
- i-Size seats up to 105cm, which is about four
- Belt fitted or ISOfix seats up to 125cm, around six or seven years
- i-Size high back boosters up to 150cm or twelve years
Infant carriers and harnessed seats up to 105 and 125cm do still have a seat-specific weight limit which can be found on the orange sticker on the back of the seat, and this limit must not be exceeded.
A few examples of R129 car seats
40 to 83cm (13kg)Rear facing car seat from birth to about 15 months. This seat can also be belt fitted without the ISOfix base.
61 to 105cm (18kg)Rear facing from 6 months to about 4 years
61 to 125cm (36kg)Rear facing from 6 months to about 7 years
Most infant seats have a base that can also be used for a bigger seat up to 105cm for older children.
ECE R44/04 weight groups
Group 0, from 0-10kg, birth to 9 months
Group 0+ from 0-13kg, birth to 15 months
Group 1 from 9-18kg, 9 months to 4 years
Group 2 from 15-25kg, 3 to 7 years
Group 3 from 22-36kg, 6 to 12 years *
Group 0, Birth to 10kgThis is a car bed, which is suitable for the first six months. They are particularly good for premature babies who can suffer breathing difficulties in more upright seats. They take up two spaces in the car as they are installed sideways. Not many manufacturers make car beds and unless the baby needs one for medical reasons, we believe that travelling backwards is safer than travelling sideways.
Group 0+, Birth to 13kgRear facing infant carrier car seat, for babies from birth up to about 15 months. Most pushchair manufacturers make adapters which allow you to use these car seats as part of a travel system.
Group 1, 9-18kgCar seat with a five-point harness for children aged approximately 9 months to 4 years. There are no car seats available anymore that are Group 1 only, extended rear facing seats are all combination seats which cover more than one group.
Group 2, 15-25kg Car seat with a harness up to 25kg. There are no seats available which are Group 2 only, most are Group 1-2, 9-25kg.
Group 2-3, 15-36kgSeat belt positioning high back booster seat. The head rest can be moved up to grow with the child, and in some models the sides move outwards to give a bigger child's shoulders more room. These seats are for children aged 4 to 12. In some models the back can be removed to leave a booster cushion.
Group 3, 22-36kgBelt positioning booster cushion. These booster cushions used to be Group 2-3, but they offer no protection for a child in Group 2, so since early 2017 all new booster cushions have been approved for Group 3 only, and must only used by children who are taller than 125cm and weigh more than 22kg.
* You should choose your child's car seat according to their height and weight, and use it up to its limits. All children are different and the age given is just a rough idea of how long you can expect a seat to last, based on an average 50th percentile child. Children only grow out of their car seat by weight or height, never by age.
But the age at which they can start using a seat is important. The regulations' 9 and 15 months minimum forward facing ages are far too young. Regardless of how big or heavy they are, the bones in a child's neck and spine don't begin to fuse together until they are between two and three years old, and it takes about three years for this process to complete. So it isn't actually until they are six that their neck is strong enough to cope with the forces of a car crash. This is why it is important for children to travel rear facing for as long as possible.
The same applies to the move from rear facing seat to high back booster. Although according to the regulations a child can go into a booster seat at 15kg or 100cm, a lot of children reach that weight or height long before they are physically strong, and mentally mature enough to sit in a booster seat. We recommend rear facing until 125cm, which on average is between six and seven.
When this picture was taken in 2011, this 93rd percentile baby was six months old. He already weighed 9.5kg, so legally he was 'heavy enough' to face forward. A perfect example of the fact that legal doesn't necessarily mean safe... (This car seat was a combination one which he only used rear facing.)
Combination car seats
Apart from Group 0+ infant seats, most car seats cover more than one weight group. There are lots of different combination seats available, these are just a few examples.
Group 0-1Rear facing from birth to 18kg, forward facing from 9-18kg
Group 0-1-2Rear facing from birth to 25kg
Group 0-1-2-3Rear facing from birth to 18kg, forward facing from 9-18kg, high back booster from 15-36kg
Group 1-2Rear facing from 9-25kg
Group 1-2-3Forward facing with the five-point harness from 9-18kg, high back booster from 15-36kg
Group 1-2-3Forward facing with an impact shield from 9-18kg, high back booster from 15-36kg