Child car seat rules in Australia, from birth to seven

Australian child car seat rules set a minimum age for each stage, not the right age. The law allows a forward-facing seat from six months, while the Child Restraint Evaluation Program recommends waiting until around 30 months. Here’s what each age requires, and where the law stops.

What car seat does the law require at each age?

The law ties the restraint to the child’s age in three steps: rearward facing to six months, a restraint with an inbuilt harness from six months to four years, and either a harness or an approved booster from four to seven. Those steps are set out by the Child Restraint Evaluation Program, which tests and rates the restraints sold here.

From six months to under four years, your child can stay rearward facing or move to a forward-facing seat, but it has to have an inbuilt harness rather than relying on the car’s own seatbelt. From four to under seven, a forward-facing harnessed restraint and an approved booster both satisfy the law.

Where the child sits matters too. A child under four cannot legally sit in the front seat of a car with two or more rows. A child aged four to under seven can only sit in the front if every other back seat is already taken by a child younger than seven in an approved restraint.

Penalties are set state by state. In Queensland the fine is $1,295 plus four demerit points for each child who is not properly restrained, and the Queensland Government doubles the demerits for a second offence within a year of the first. The rule applies whenever the car is moving or stopped in traffic, such as at a red light, though not when it is parked.

Can you use a child car seat bought overseas?

No. The Child Restraint Evaluation Program says a seat bought overseas is illegal to use in Australia, because it does not comply with AS/NZS 1754, the Australian and New Zealand child restraint standard, and because it is not built to work with the top tether system used in Australian cars. The Queensland Government puts it the same way: an imported restraint cannot be used unless it complies with AS/NZS 1754. It is the same compliance trap that catches vehicles themselves, which is why the rules around grey imports are worth understanding before you buy one.

You do not need the newest edition of the standard, though. A car seat bought overseas is illegal here, while a seat built to the 2000 edition of AS/NZS 1754 is still legal to use. The current version is AS/NZS 1754:2024, published on 30 September 2024, and the Child Restraint Evaluation Program confirms the 2000, 2004, 2010, 2013 and 2024 editions are all accepted across most of the country. Look for the standards label on the restraint and the compliance wording on the box.

Second-hand seats need more care. Get hold of the manufacturer’s instructions before you fit one you did not buy new, and read the sticker on the shell, which the Queensland Government notes carries both the approval and the date the seat was made.

When should you move your child up to the next seat?

Later than the law allows, in almost every case. The age ranges are legal minimums, and the Child Restraint Evaluation Program recommends keeping a child rearward facing until around 30 months, five times longer than the six months the law demands.

Moving up is driven by fit, not birthdays. A child who has outgrown their restraint can move to the next type, but one who is still too small for the next type should stay where they are until it is safe to change.

The Child Restraint Evaluation Program lists three signs a child has outgrown a booster:

• Their shoulders no longer fit comfortably inside the booster.
• Their eye level sits above the top of the booster’s back.
• Their shoulders have passed the booster’s upper shoulder-height markers.

An adult lap-sash seatbelt is generally only a proper fit once a child reaches 145cm tall, according to the Child Restraint Evaluation Program. Most children do not get there until well into primary school.

The same organisation publishes a five-step test for working out whether your child is ready for a belt alone, set out in the Child Restraint Evaluation Program’s guidance for parents:

• They sit all the way back against the vehicle seat back.
• Their knees bend comfortably over the front edge of the seat.
• The sash belt crosses the middle of the shoulder.
• The lap belt sits low across the top of the thighs.
• They can hold that position for the whole trip.

If any step fails, your child still needs a booster. The law from seven onwards is looser, but South Australia’s road rules require every child under 16 to be in a suitable approved restraint or a properly adjusted seatbelt, and for children aged seven to 16 who are too small for a belt, the Child Restraint Evaluation Program strongly recommends staying in a harnessed restraint, a booster, or an approved child harness used with the seatbelt.

Do you need ISOFIX, or will a top tether do?

You need the top tether either way. ISOFIX, a pair of rigid or flexible connectors that clip onto metal anchor bars built into the car’s seat, replaces the seatbelt as the way the restraint is held down, not the top tether strap that runs from the top of the restraint to an anchor point behind the seat. Every Australian rearward and forward-facing child car seat, ISOFIX models included, must use that strap, according to the Child Restraint Evaluation Program.

An ISOFIX compatible seat is not locked to ISOFIX positions. Put the same seat in a seating position without lower anchorages and you install it with the vehicle seatbelt and the top tether instead. That flexibility matters if you move the seat between cars or need three restraints across a back row.

One thing ISOFIX will not solve is the booster stage. There is no ISOFIX compatible booster seat available in Australia, the Child Restraint Evaluation Program says, so once your child moves to a booster, the car’s seatbelt does all the work of holding both the booster and the child.

Where can you get a child car seat checked?

At an Authorised Restraint Fitting Station, where trained fitters install and adjust the seat for you. The Child Restraint Evaluation Program lists fitting stations for three states: New South Wales through Transport for NSW, Victoria through RACV, and Western Australia through Roadwise Type 1 child car restraint fitters.

Best for any parent fitting a seat for the first time, or shifting one between cars: book a fitting station check rather than trusting the manual and a tight tug on the strap. A correctly chosen seat installed loosely is not a correctly restrained child.

Hire cars are covered by the same rules. In Queensland, a rental vehicle has to meet the child restraint requirements exactly as your own car does, so budget the time to fit the seat properly at the depot. If the hire car is for a long trip, the rules on where you can legally stop and sleep overnight are worth sorting out at the same time.

The short version: follow the age steps to stay legal, then ignore them and follow the fit. Your child outgrows a seat when their body says so, and in Australia that is almost always later than their birthday suggests.