The question of 'do child car seats expire' can be a confusing matter. There are many differing timescales given, and car seats in the UK do not come with a stamped expiry date. It is not always clear when a car seat becomes unsafe to use, and there are car seats on the market designed to last 11 years.
Child car seats in the UK are tested to regulation 44, of which there have been several amendments. These are shown as R44.01, R44.02, R44.03 and R44.04. Child car seats may alternatively be tested to the new car seat regulation R129 (iSize). Car seats tested to R44.01 or R44.02, are now illegal to sell and use, and car seats which have been tested to R44.03 are likely to be quite old.
R44.03 was introduced in 1995, so seats carrying this approval could be up to 20 years old!
Both of these car seats carry R44.03 approval labels!
Many manufacturers recommend that you replace or upgrade your child car seats after 5 years, because child car seats are constantly being improved and upgraded, and a new car seat will be able to provide better protection and comfort than an older car seat. A good example of this is the increased availability of Swedish extended rear facing car seats in the UK, or new iSize seats.
Swedish rear facing car seats, which prolong the excellent safety offered by rear facing.
New iSize car seats pass more stringent testing such as side impact testing, and also require children to rear face for longer.
Child car seats should not be used for more than 6-10 years, which was a recommendation from America that has been adopted throughout Europe. Over time, the materials of a car seat will begin to degrade, so an old car seat may not perform as it should do in a collision.
It does not mean that car seats which are more than 10 years old are dangerous to use, provided they meet the correct regulation, are in good condition, with the harness intact and they are fitted and used correctly (and suitable for the child). However, there have been large advances in child car seat safety and a newer seat will provide the very best protection.