Fitting a child car seat with a 3-point adult seat belt is the most traditional way of securing a car seat. However, ISOFIX seats (which we’ll cover below) are growing in popularity thanks to the safety and security they offer.

Although it may look a bit daunting, reading the car seat instruction booklet is an essential first step before securing your child’s car seat with a seat belt. We also recommend familiarising yourself with the child safety section of your car manual, which outlines additional information about how to best keep your child safe in the car.

Maxi-Cosi Rock Car Seat (Essential Black)

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Once you’ve read the instruction manual, you can refer to these tips to make the installation a bit easier:

• When placing the car seat in the vehicle, check that it sits squarely and evenly on the base of the seat.

• Ensure the seat belt passes through the correct route guides on the car seat. (If you’re installing a rear-facing seat, it must go through the blue guides. If your seat is forward-facing, it will go through the red guides).

• Once you’ve taken the top part of the seat belt around the back, pull to tighten the seat belt to make sure it’s secure the whole way around.

• Take a moment to check the entire seat belt; there should be no slack or twists at any point.

• Activate any lock-off devices and tension levers or buttons. These systems will help the seat belt fit more tightly, and prevent it from slipping.

• Ensure the seat moves no more than one inch in any direction.

• Check that the carry handle is in the right position (which varies for different car seats) and that the seat belt buckle doesn’t bend around the frame of the car seat.

As with any car seat, it’s best to carefully follow the manufacturer’s instructions, and seek professional help if you’re ever unsure about anything.

i-Size car seats are designed to be fitted to your vehicle using a standardised system called ISOFIX. This system works by attaching the car seat onto small metal bars, or anchor points, which can typically be found where the back seat and seat cushion meet.

Most newer cars are equipped with ISOFIX connectors, and this system is generally considered the safest fitting option. Best of all, this type of car seat fitting makes the installation process significantly easier.

Cybex Sirona S Car Seat (Manhattan Grey)

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After you’ve located the ISOFIX prongs on the back of the car seat, you simply need to plug the connectors into the corresponding anchor points in your car. You’ll hear an audible “click” when they’re connected, and many seats also come with an indicator light that turns green when secured correctly.

On some seats, a third anchor point is needed (such as a supporting leg which extends from the seat down to the car’s floor for certain baby car seats). If you’re using a child seat with a supporting leg, ensure it’s correctly adjusted, so the seat is braced against the floor.

The key thing to remember is that ISOFIX was introduced to make fitting a car seat much easier, and to lower the risk of installing it incorrectly. That being said, ISOFIX bases aren’t compatible with every vehicle, so it’s best to check suitability with your manufacturer.