The cheapest London Gatwick to San Juan return flight on the radar right now is £680, flying with TAP Air Portugal + jetBlue + Virgin Atlantic via one or more connections. It covers departures in January 2027, and every dated link below opens that exact LGW–SJU search on Skyscanner. That is roughly 12% below the £774 this route usually costs. Across 109 recorded checks it has ranged between £472 and £1,274. Our sampling points to January 2027 as the cheapest month to fly London Gatwick to San Juan.
We do not post a price and leave it to age. Each fare is re-checked against Skyscanner on a schedule and carries the time it was last confirmed. Not flying from London Gatwick? We track 54 other departure cities for San Juan, listed at the foot of this page.
Cheap fares do not hang around. If this one has already gone, nudge the dates either way by a day or two; London Gatwick to San Juan is usually still decent value around the same window.