Child car seats

By law, children aged up to at least 7 years must use a child car seat when travelling in motor vehicles in Australia.

The right type of car seat for your child depends on their age and size, as well as any additional needs. It’s always safest to keep your child in the car seat that’s most appropriate for your child’s size, regardless of age.

For more information about child car seat standards, laws and exemptions, see our articles on choosing and installing child car seats and safe car travel for children with disability, medical conditions or other needs.

Types of child car seats

Rear-facing child car seat or infant capsule
This:

• faces towards the back of the car
• has an inbuilt harness.

An ‘extended rear-facing seat’ is one that children can use until they’re 2-3 years old.

Forward-facing child car seat
This:

• faces towards the front of the car
• has an inbuilt harness.

An ‘extended harnessed seat’ is one that has an inbuilt harness that fits most children until they’re 7-8 years old.

Booster seat
This:

• faces towards the front of the car
• does not have an inbuilt harness
• is usually used with an adult lap-sash seatbelt.

If you can’t put the booster seat where there’s a lap-sash adult seatbelt, you must use a child safety harness as well as the lap-only seatbelt.

If you need to use a child safety harness with your booster seat, make sure the shoulder straps aren’t too tight. Also make sure that the lap-only part of the seatbelt is secured low across your child’s thighs below their hips.

Only some booster seats accommodate a child safety harness. These booster seats are designed to make sure that the harness can’t slip up into your child’s tummy in a crash. Check the booster seat instructions.

Convertible child car seat
This means the car seat can be configured as a rear-facing car seat or a forward-facing seat with an inbuilt harness.

Combination child car seat
This means the car seat can be configured as a forward-facing car seat with inbuilt harness or a booster seat with a lap-sash adult seatbelt.

Birth to 6 months

Your baby must use a rear-facing child car seat with an inbuilt harness for at least the first 6 months of life. This is the minimum legal requirement.

You can use one of the following:

• a car seat designed specifically for the first 6 months, like an infant capsule
• a convertible car seat, which must be configured as rear facing.

Babies outgrow infant capsules quickly, so you might want to hire rather than buy one. You could look into hiring an approved infant capsule from your local council, ambulance service or a private company. It’s a good idea to do this well before your baby is born.

6 months-4 years

If your child is aged 6 months up to 4 years, they must use one of the following as a minimum legal requirement:

• a rear-facing child car seat with an inbuilt harness
• a forward-facing child car seat with an inbuilt harness.

It’s recommended that children use rear-facing car seats until they’re at least 12 months old. Rear-facing car seats give children the head and neck support that they need to stay safe.

Children can move to forward-facing car seats only when their shoulders reach the maximum shoulder height markers on their rear-facing car seat.

Some rear-facing car seats have one shoulder height marker. Others have 2 markers that show the minimum and maximum shoulder height for moving to a forward-facing seat. If your child has a car seat with 2 markers, keep your child in this car seat until they reach the maximum shoulder height marker.

4-7 years

If your child is aged 4 years up to 7 years, they must use one of the following as a minimum legal requirement:

• a forward-facing child car seat with an inbuilt harness
• a booster seat with a lap-sash adult seatbelt or child safety harness.

If your child outgrows a forward-facing car seat, they can move to a booster seat. Your child has outgrown the car seat when they reach the maximum shoulder height marker.

7 years and older

If your child is aged 7 years or older, they must use one of the following as a minimum legal requirement:

• a booster seat with a lap-sash adult seatbelt or child safety harness
• a vehicle seat with a properly adjusted and fastened lap-sash adult seatbelt.

Some children at this age might still fit into forward-facing car seats with inbuilt harnesses.

If your child has reached the top shoulder height markers on a booster seat, try the 5-point seatbelt test. This will tell you whether your child can use a lap-sash adult seatbelt correctly and safely. If your child has outgrown their current booster seat but doesn’t fit the seatbelt correctly, you’ll need to get a taller booster seat.

Lap-sash adult seatbelts: the 5-step test

Most 7-year-olds are too small for lap-sash adult seatbelts, even though Australian law says that they can use them. This is because lap-sash adult seatbelts are designed for people who are at least 145 cm tall, and many children don’t reach this height until they’re 10-12 years old.

Your child can start using a lap-sash adult seatbelt only when they pass the 5-step test.

To pass the 5-step test, your child must be able to do all of the following:

1. Sit with their back firmly against the seat back.
2. Bend their knees comfortably over the front of the seat cushion.
3. Sit with the sash belt across their mid-shoulder, not across their face or neck.
4. Sit with the lap belt across the top of their thighs, not across their abdomen.
5. Stay in this position for the whole car trip.

A lap-sash adult seatbelt might fit your child correctly only in certain vehicles or vehicle seats. For example, the seatbelt might fit your child better when they’re sitting in the middle vehicle seat rather than the outer seat.

If a police officer thinks that a child aged over 7 years isn’t wearing a lap-sash adult seatbelt correctly, the officer can give you a fine and penalty points recorded against your driver licence.

For advice about moving your child into a different car seat, it’s a good idea to ask your child and family health nurse or other health professional, your local fitting service, or your state or territory Kidsafe or road safety authority.

Changing child car seats: size and safety considerations

It’s always safest to keep your child in the child car seat that’s most appropriate for your child’s size, regardless of age. Therefore, the Australian law allows for the following:

• Children who are too small for the type of car seat specified for their age can stay in their current car seat until they grow into the seat for the next age group.
• Children who are too big for the type of car seat specified for their age can move to the seat specified for the next age group.

If your child moves to the next type of car seat or starts using a lap-sash adult seat belt before they’re big enough, they might not be protected properly in a crash.