A Basic Guide to Car Seat Sizes

Car safety for kids is vitally important and many parents are unclear about which seat is correct for their child. Some seats are more complex to fit than others, and it is always worth visiting retailers who offer car seat fitting services for your complete peace of mind.

The UK law states that your child must use the appropriate car seat until they are either aged 12 or reach 135cm in height.  Here is a basic guide to the different types of car seat available:

From birth to 12-15 months (up to 13kg)

You need an infant car seat which should be rearward facing. These seats often come with a carry handle so that your can easily transfer your sleeping baby from the car to wherever you are going without disturbing them. For this reason, go for a portable type that is not too heavy. Some of the latest infant car seats come with Isofix fittings for easy installation into Isofix compatible cars. (Ask your retailer for further information on Isofix.)

From birth to 4 years (18kg)

You can purchase combination car seats that are suitable for newborns (9kg) up to around age 4 (18kg). These are often not as portable as the infant seats. You install them to be rearward-facing until your child is 9kg after which they can be forward-facing. Always follow your car and seat manufacturer’s advice about seat positioning and installation with particular attention to airbags.


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From around 9 months to 4 years (9-18kg)

Forward-facing seats are available for this weight group and many models are Isofix compatible. They are often padded for extra comfort offering adjustable recline positions. They are not very portable and tend to stay fixed in your car.

From 9 months to 11 years (9-36kg)

High back booster seats with harnesses  can later be used with your car’s seatbelt as your child grows. High back boosters are forward-facing.

From 4 – 11 years (15-36kg)

You can buy high back booster seats without harnesses which means that from day one, they are secured with an adult seatbelt and/or Isofix attachment.

From 4 – 11 (15-36kg)

Booster seats are secured with the adult seatbelt in the back seat of your car. These are very portable and it is useful to have an extra one as a back up seat for those unexpected journeys with grandparents and so forth. Booster seats are not suitable for babies.


Still looking for the perfect car seat?

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