To use your Oyster card on the Gatwick Express, simply "touch in" on the yellow card reader at the ticket gates at London Victoria and "touch out" at Gatwick Airport (or vice versa). The journey is part of the "pay as you go" (PAYG) extension to Gatwick, meaning you don't need a paper ticket. However, be cautious: the Gatwick Express is significantly more expensive than the standard Southern or Thameslink services that run the same route. The system identifies which train you took based on the platforms and gates you use at Victoria; Gatwick Express usually operates from platforms 13 and 14. Ensure your card has sufficient credit for the premium fare, as the Gatwick Express fare is automatically deducted. Note that while daily caps apply, the "Gatwick Express" specific fare is higher than the standard rail cap, so it may not always be the cheapest way to travel between the city and the airport in 2026.