AirHint found the following cheapest one-way flights from Washington (IAD) to San Jose (SJO) in September 2025 (see full year).
One-Way flights
| 23 Sep | Volaris El Salvador | ||
| 25 Sep | United | ||
| 26 Sep | United | ||
| 17 Sep | Volaris El Salvador | ||
| 21 Sep | Volaris El Salvador | ||
| 20 Sep | Copa | ||
| 22 Sep | Copa | ||
| 28 Sep | Copa | ||
| 18 Sep | Avianca | ||
| 19 Sep | Copa |
Also check the deals for return flights from Washington to San Jose in September.
The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.
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