What is ISOFIX?

Whilst you are shopping around for car seats for your child, you may come across the term ISOFIX but what exactly is it? In short, it’s an attachment point built into the car rather than the seat belt and below, we discuss the system in detail.

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What is ISOFIX
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The term ISOFIX stands for “International Standards Organisation Fix” and the system became mandatory in all vehicles manufactured after November 2014 (section 19A). During your search for baby car seats, you will certainly come across it and below we show you what it is and why ISOFIX in car seats is very beneficial.

What is ISOFIX?

ISOFIX is a universal method of fitting car seats and it uses an attachment point that’s built into the car rather than the seat belt. This makes installing a car seat more user-friendly and it also reduces the chances of making errors. As you can see in the above image, there are two attachment points labelled with ISOFIX for each rear seat.

Types of ISOFIX Car Seats

There are three main types of ISOFIX car seats that you can use to install your baby’s car seat and these include a vehicle-specific, semi-universal and universal type.

  • Universal – Suitable for most modern cars that use a two-point connection and top tether.
  • Semi-universal – Only compatible with certain vehicles that cater for either a top tether or foot prop.
  • Vehicle Specific – Only compatible with certain vehicles that use only the two-point connection.

In terms of the two-point connections, circled in red in the below photo is what the seat uses to connect.

what is isofix car seat

Benefits of ISOFIX

Although ISOFIX car seats often come with a premium price tag when compared to 3-point seat belt alternatives, they are a worthwhile investment. Some of the benefits of ISOFIX car seats include:

  • Reduces the risk of installing the seat incorrectly
  • Creates a rigid connection between the seat and the car itself
  • Far less movement in the event of side impact
  • Easier to install, remove and switch between cars
  • Provides peace of mind that the seat is securely in place

Drawbacks of ISOFIX

The only main downside of the ISOFIX system is the fact that not all cars are compatible. For example, if you are a family with multiple cars and one of the cars isn’t compatible, it may become an issue when sharing the seat.


Due to the fact that ISOFIX became a mandatory feature in all cars since 2014, there will be more and more ISOFIX car seats being made available. Unless you drive an older vehicle, the ISOFIX system is the number 1 feature you should look for in a car seat and it comes with plenty of benefits that will make paying the slight increase in price worthwhile.

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