What is ISOFix?

ISOFix is a child restraint system. ISOFix stands for "International Standards Organisation FIX". ISOFix points are anchorage points in a car's structure into which an ISOFix child seat can simply be plugged. It is intended to make fitting child seats quick and simple.

New vehicles have ISOFix points built in when they are manufactured, and child seat manufacturers are producing ISOFix child seats which have been approved for use in specific car models.

Their main advantage is that they allow a child restraint to be fixed safely to the main structure of the car, helping minimise the risk of poor or incorrect installation which is common with the use of adult belts.

Having permanent fixtures in each seat position also means that ISOFix compatible child restraints with ISOFix fittings will be able to be fitted and released very easily without needing to use the adult seat belts.

Check with product manufacturers which seats have them and which cars they fit. We still advise you to try a car seat out in your car before you buy it, as it is not yet the case that an ISOFix seat will fit in every car with ISOFix points. Your vehicle's handbook will provide detailed information on which size child restraint may be used in that vehicle as well as instructions on attaching the seat to the anchorage points.

Further reading

Childcareseats.org.uk - Isofix Seats
Advice last checked: 05 February 2018 Next check due: 05 February 2021

All advice is either supported by references (cited in the text) or is based upon peer reviewed professional opinion. Our advice is impartial and not influenced by sponsors or product suppliers listed on the site.
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  1. Department for Transport: Think! 0  Child car seats
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