$129 Cheap Delta flights San Diego (SAN) to St. Louis (STL)

You'll find cheap round-trip Delta Air Lines flights from $231 from SAN to STL by filtering your results from "Price (lowest to highest)" on Expedia. Or look for deals from $129 for a one-way journey.**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.

Begin your search one to three months before your departure to find cheap fares on Delta Air Lines flights from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also cut costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Time it well, and you can enjoy significant savings on domestic journeys.*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 Delta Air Lines's earliest flights from SAN to STL by checking the "Early Morning" and "Morning" filters. Not only will you arrive at 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.

Jetting off from SAN to STL with Delta Air Lines comes with a host of benefits, including a rewarding loyalty program and an excellent in-flight experience. Plus, when booking through Expedia, One Key™ members can earn OneKeyCash™* to redeem on select future travel purchases. That's in addition to the Delta SkyMiles points you can earn with Delta Air Lines.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.