Cheap Spirit Airlines flights Boise (BOI) to San Diego (SAN)

Landing cheap one-way Spirit Airlines flights from BOI to SAN on Expedia couldn't be easier — just filter by "Price (lowest to highest)." Or check out our affordable round-trip fares for your next getaway.**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 find cheap Spirit Airlines fares from Boise Airport (BOI) to San Diego Intl. Airport (SAN), start searching one to three months before your intended departure. Reserving domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also affect the price you pay. Sunday is usually the most affordable, while Monday is often the most expensive for domestic flights. You can save 6% on average by choosing to book on a Sunday.**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.

Browse Spirit Airlines's earliest flights from BOI to SAN by checking the "Early Morning" and "Morning" filters. Not only will you get to your destination 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.

Journey from BOI to SAN with Spirit Airlines and look forward to a range 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.