The monetary ones (1p/2p/50p et al.) don't expire either, you just need to meet the cost at the time you use them. (Exactly like cash in that sense: loses value

The monetary ones (1p/2p/50p et al.) don't expire either, you just need to meet the cost at the time you use them. (Exactly like cash in that sense: loses value with inflation, but you can still use what you have, just for less.)