The cheapest London Gatwick to Seoul return flight on the radar right now is £718, flying with Air China + China Southern via one or more connections. It covers departures in September 2026, and every dated link below opens that exact LGW–ICN search on Skyscanner. The price we usually record on this route is £504. Across 71 recorded checks it has ranged between £406 and £811. Our sampling points to September 2026 as the cheapest month to fly London Gatwick to Seoul.
Prices are re-checked against Skyscanner automatically, and every one shows when it was last confirmed, so nothing here is older than it looks. Not flying from London Gatwick? We track 61 other departure cities for Seoul, listed at the foot of this page.
Prices like this tend to vanish fast. If it has gone when you look, try the days either side of the dates above, since London Gatwick to Seoul is often still worth booking within a day or two of the fare we found.