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

https://dlf-ne.org/is-paying-two-barrier-fees-ever-the-right-move-at-uk-airports/

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