Dropping someone off at a UK airport can cost around £6.51 on average, but...

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

Dropping someone off at a UK airport can cost around £6.51 on average, but places like Gatwick can hit £10, and Heathrow around £7. We’ll break down how these fees compare to parking, including free windows at Long Stay and Park & Ride lots