Safety: Child car seats

  • In Australia, car and other transport crashes are the single biggest cause of death of children under 15 years of age. Each year in Victoria, hundreds of children are involved in car crashes, and in these moments their risk of serious injury is significantly increased if they are unrestrained in the car, not restrained correctly or were travelling in the front seat of the car.

    Whenever they are riding in a car, it is very important to ensure your child is in the correct restraint for their height.

    Which car restraint is best for my child?

    The best car seat for your child is one that fits. Children should always travel in a restraint matched to their height, not their age. Don’t be tempted to move your child into the next restraint type too quickly, even if age-based laws would allow it. 

    You should wait until your child outgrows their restraint before moving them into a bigger one. Use the shoulder-height indicators on the restraint to tell you when your child has outgrown it. 

    • Always follow the manufacturer’s instructions to ensure the restraint is suitable for your child and is installed correctly into your car. 
    • Restraints should be regularly checked and adjusted as your child grows. 
    • Make sure your child is buckled in properly, using the correct seat-belt or harness type for their size, even if it is only a short trip. 
    • All car seats should comply with the Australian and New Zealand Standard AS/NZS 1754. It is illegal to use an overseas model or restraint that doesn’t meet this standard.

    When to change restraints

    Moving your child too early to the next restraint type increases their risk of serious injury or death in the event of a car crash. 

    Most Australian car restraint laws are based on a child’s age. However, The Royal Children’s Hospital and national expert guidelines recommend you choose a restraint that best fits your child’s height, rather than their age. 

    For most children, height-based recommendations will keep them in each type of car seat for longer, but also keep them safer. 

    For current legal requirements and recommendations on car restraints or booster seats for children in Victoria, visit the VicRoads website.

    Moving to a forward-facing restraint

    Babies are safest in a rear-facing restraint, and would only be expected to outgrow these restraints when they are two to three years old. 

    Children should stay rear-facing for as long as possible. As your child grows, it may appear that there is no room for their legs when they are restrained in this position. However, it is OK for them to hang their legs out the sides, have their legs crossed, be tucked into their body, or kicked straight up on the seat in front of them. Facing rearwards (despite having their legs in a seemingly strange position) is still the safest position for them to travel. 

    You should only move your child to a forward-facing restraint with inbuilt harnesses when the maximum height requirement on your rear-facing restraint is reached. 

    Age Australian laws RCH recommendation
    Under 6 months Rear-facing only Rear-facing only
    Six months to four years Rear- or forward-facing with harness Rear-facing for a long as possible. Use height/length (not age) to determine when to change restraints

    Moving into a booster seat

    Only move your child into a booster seat with an adult seat belt when they are too tall for a forward-facing restraint, as shown by the shoulder markers. The average Australian child will not outgrow a forward-facing restraint until they are eight years old, and some children may be even older. 

    To be safest in a crash, your child needs to be in a booster seat until they are at least 145 cm tall and can pass the five-step safety test (see below). On average, Australian children will not reach a height of 145 cm until about 11 years of age. 

    Age Australian laws RCH recommendation
    Four to seven years Forward-facing with inbuilt harness or booster seat Forward-facing with inbuilt harness for as long as possible. Use height (not age) to determine when to move into booster seat
    Seven years and older  Booster or adult seat Booster seat until child is 145 cm or taller and can pass the five-step safety test

    Moving into adult seats

    If your child is 145 cm or over, they will be ready to move to an adult seat when they can answer ‘yes’ to all of the questions in the five-step safety test: 

    The five-step safety test

    1. Can the child sit with their back against the vehicle seat? 
    2. Do the child’s knees bend over the edge of the seat? 
    3. Does the seat-belt sit across the middle of their shoulder (not on the neck or out near the arm)? 
    4. Is the lap belt sitting low across the hips, touching the thighs? 
    5. Can the child stay seated like this for the whole trip? 

    Moving into the front seat

    It is recommended children sit in the back seat until they are older than 12 years as it is safer and offers more protection to passengers than the front seat.

    Look before you lock

    Anyone can accidentally leave their child in the car, especially when tired, stressed, distracted or there is a change in routine. Usually they remember quickly and no harm is done; however, there have been instances where young children have been left in the car for extended periods, with devastating consequences. 

    Even on cool days, the temperature inside a car can quickly rise to dangerous levels. If children are left in hot cars, they may be at risk of dehydration, heatstroke or even death. 

    Get in the habit of always checking the back seat before locking the car door, even if you know no one is in there. You can also try techniques such as always placing your bag, phone or wallet in the back seat of the car when you drive. For more information and tips see Look Before You Lock.

    Key points to remember

    • All car seats must comply with the appropriate Australian and New Zealand Standard AS/NZS 1754. 
    • Ensure your child always travels in the right size restraint for their height. 
    • Ensure your child is always correctly restrained in their car seat, even if it is only a short trip. 
    • Children need to be at least 145 cm and pass the 5-step safety test before travelling in an adult seat. 
    • Always look to make sure all children are out before locking up and leaving the car.

    For more information

    Common questions our doctors are asked

    I have recently found that my car restraint doesn’t have a high safety rating. What do you suggest?

    Any car restraint that complies with the Australian safety standards meets minimum safety requirements and is safe to use – you do not need to rely on additional safety ratings, expensive brands or marketed safety features.

    What is important is that the car seat is installed correctly in your vehicle, and that your child is appropriately restrained in a car seat that is most suitable for their height.

    My nine-year-old doesn’t want to use a booster seat because his friends don’t, even though they are all shorter than the recommended height. What should I do?

    Any child, no matter their age, should be 145 cm or taller and pass the five-step safety test before moving into an adult seat with a lap-sash seat belt. While it’s usual for children at this age to be influenced by their friends, it is you, as the parent, who is responsible for their safety. Take the time to discuss with your child why it is important that they stay in a booster seat, and try not to put convenience above safety. 

    Can I use the integrated booster seat that is built into my car, or is it safer to buy a separate booster seat or booster cushion that needs to be installed?

    The law in Victoria allows children four years or older to use integrated booster seats. While integrated booster seats have potential benefits of not relying on the correct installation by a parent or fitter, they also have potential risks due to lack of back support or head protection.

    The RCH recommends using either a booster seat or integrated booster seat until a child reaches 145cm and passes the five-step safety test.

    Booster cushions are not recommended as they do not offer back support and cannot be anchored to the car. Booster cushions are no longer manufactured in Australia, and while they are legal to use, they offer less protection.

    Check with relevant regulatory bodies for specific car seat safety laws in your state.

    Does my baby need to travel in a car seat when I’m in a taxi? What about when in a rideshare service like Uber? 

    In all Australian states and territories except New South Wales, children can travel in a taxi without a child restraint. Babies aged under 12 months must travel in the backseat, be held by an adult, but not share the seatbelt. Children aged one to seven years must sit in the backseat and should use a seatbelt. In New South Wales, children under 12 months must use a child restraint in a taxi.

    In Victoria, children should be restrained properly when using rideshare services – legally, the rules that apply to private vehicles also apply to rideshare vehicles.

    The RCH recommends that all children be appropriately restrained in a suitable car restraint appropriate for their height whenever travelling in a vehicle. This may mean that you need to take your own car seat with you when travelling and know how to install it appropriately into another vehicle – although this may seem impractical and involve more planning, it is the safest option for your child.

    Developed by The Royal Children's Hospital Community Information in consultation with the Trauma Service. We acknowledge the input of RCH consumers and carers. 

    Reviewed May 2019. 

    This information is awaiting routine review. Please always seek the most recent advice from a registered and practising clinician.

    Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit


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