$141 Cheap Southwest Airlines flights Raleigh (RDU) to San Juan (SJU)

Landing cheap one-way Southwest Airlines flights from RDU to SJU from $141 on Expedia is a cinch — just filter by "Price (lowest to highest)." Or check out our affordable round-trip fares from $261 for your next exciting adventure.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

To discover cheap flights from RDU to SJU with Southwest Airlines, start your search about one month before your intended departure. You can save 17% when you lock in your international tickets 18 to 29 days ahead instead of booking four to five months in advance. Another good tip? Booking on Sunday offers average savings of 17% compared to Friday (the most expensive day).**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Search Southwest Airlines's earliest flights from RDU to SJU by checking the "Morning" and "Early Morning" filters. Not only will you get to where you're going sooner, early departures also experience 20% fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.