The cheapest Rome to San Juan return flight on the radar right now is €771, flying with Air France + KLM via one or more connections. It covers departures in November 2026, and every dated link below opens that exact FCO–SJU search on Skyscanner. Across 69 recorded checks it has ranged between €488 and €1,327. Our sampling points to November 2026 as the cheapest month to fly Rome to San Juan.
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 Rome? We track 53 other departure cities for San Juan, 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 Rome to San Juan is often still worth booking within a day or two of the fare we found.