Leaving from inside the island: You don’t have to call a taxi to the festival area. City Taxi will be at Sziget during the whole week, operating a taxi station, so you don’t have to call one yourself. Find them at the K-bridge entrance parking lot (from the inside, don't have to cross the bridge).

Leaving from outside the island: If you cross the K-bridge you will also find a taxi station next to the ticket booths, where Budapest Taxi will take you home.

If you have any questions please look for the staff at the taxi station on the island or call the central number of City Taxi (non-stop)
(+ 36 1) 2 111 111.

More:
Szigetfestival.com/info/festival_info