$143 Cheap Spirit Airlines flights Boston (BOS) to San Diego (SAN)

Set the "Price (lowest to highest)" filter on Expedia to look for cheap Spirit Airlines return flights from $261 from BOS to SAN. Affordable one-way fares from $143 are also on offer.**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.

Search for cheap Spirit Airlines flights from Logan Intl. Airport (BOS) to San Diego Intl. Airport (SAN) one to three months prior to your departure. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. No matter the fare type and journey, the ideal day to book a domestic flight is generally Sunday and the most expensive day tends to be Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**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.

Sort your results by "Morning" and "Early Morning" to see the earliest departures from BOS to SAN. Jetting off early means flight cancellations are less likely.**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.

Journey from BOS to SAN with Spirit Airlines and enjoy a host of benefits starting with a rewarding loyalty program. When booking through Expedia as a Free Spirit and One Key™ member, you may also earn OneKeyCash™* to spend on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.