Cheapest return flights from Seattle (SEA) to San Juan (SJU), December

8 dates in December, from $ 350. Book in one tap, or check whether to buy now or wait.

One-wayReturn
Dates, airline, and price
Dates Airline Price
4 Dec 13 Dec Frontier Airlines
12 Dec 19 Dec Frontier Airlines
3 Dec 18 Dec Frontier Airlines
3 Dec 6 Dec American Airlines
15 Dec 25 Dec United
17 Dec 24 Dec Sun Country Airlines
31 Dec 4 Jan 2027 American Airlines
17 Dec 25 Dec Sun Country Airlines
Powered by

Cheapest deals for the full year

Deals for one-way flights from Seattle to San Juan in December.

Book a cheap hotel in San Juan

Cheap car rent in Luis Munoz Marin Intl

Updated Oct 10, 2026.

About these fares

These results come from our latest search across airlines for your currency. Prices change quickly and are not locked until you complete booking—always confirm the total and fare rules on the partner site.

Feel free to contact us with any feedback or request another flight research.