Dropping someone off at UK airports can mean different costs depending on where...

https://dlf-ne.org/what-is-the-free-long-stay-window-at-gatwick-airport/

Dropping someone off at UK airports can mean different costs depending on where you go — the average is around £6.51, but Gatwick’s charge hits £10, while Heathrow’s is £7. Picking up can cost extra too