How do I tell what year a car is from its number plate?

Since September 2001, UK plates have followed the format of two letters, two digits, then three letters - for example AB12 CDE. The two digits in the middle are the age identifier, and that's the part that tells you roughly when the car was first registered.

New identifiers are issued twice a year. The March batch uses the last two digits of the year as-is (2024 becomes 24). The September batch adds 50 (2024 becomes 74). So a 24 plate is March to August 2024, and a 74 plate is September 2024 to February 2025.

Plates issued before September 2001 used older systems (letter prefixes, and before that letter suffixes), so the same trick doesn't apply to genuinely older cars - the age identifier system only covers the last couple of decades.

Either way, a plate only gives you an age band, not an exact date, and a private plate can hide the age identifier altogether.