Today’s MTDD is to San Juan, Puerto Rico (SJU). Delta has roundtrip from San Francisco (SFO) to San Juan, Puerto Rico (SJU) for only $317 roundtrip. Valid for travel until November 14th, and must purchase at least 7 days before travel. Use the ITA Matrix Airfare search tool to search availabilities and then delta.com to book. Happy flying! Thanks to TheFlightDeal for the notification.