$98 Find Cheap Flights from St. Louis to San Diego - Compare and Save

Southwest operates a non-stop flight from STL to SAN. Airlines such as Frontier, United Airlines, Delta, and American Airlines operate one-stop flights from STL to SAN. Some of the layover cities include Dallas (DFW), Denver (DEN), Minneapolis (MSP), Las Vegas (LAS), and Houston (IAH). American Airlines and United Airlines are among the carriers that operate flights from STL to SAN with two layovers.

Yes. STL has installed Lactation Suites in Gates A10, C9, and E33. Each unit has a comfortable club chair with a full back and a movable arm table, a sink with counter space, and power outlets.

Yes. There are two USO lounges at STL, one in Terminal 1 at Baggage Claim M6. This lounge is open 24h. The other is in Terminal 2 near Exit 11 by Baggage Claim, open from 7 am until 6 pm. Some amenities in these lounges include showers, a sleeping area with beds, a library, a children's play area, snacks and beverages, computers, Wi-Fi, TV, comfortable seating, and more.

From Lindbergh Field at Terminal 1 at STL, you can catch a San Diego Metro Transit bus #992 into downtown San Diego at Broadway and State Street. This trip takes about 18min and buses depart about every 20min. Taxis and shuttles can get you from STL to downtown San Diego in less than half the time but at about twice the price of a bus.

Among airlines operating St. Louis to San Diego flights:

• Southwest: offers free seat selection

Extra legroom and free seat selection availability depends on fare class and route.

Only Southwest operates flights between St. Louis and San Diego.

Flights from St. Louis to San Diego usually depart from Lambert-St Louis (STL) and arrive at San Diego (SAN).

Here are some options for this route, based on selected ticket types and cabin classes:

• Southwest: a cabin bag and a checked bag in Economy Class

Bag allowance can vary by ticket type, cabin class, route and airline, so travelers should check the fare details before booking.

Three cabin classes are available on flights from St. Louis to San Diego:

• Economy Class
• Business Class
• First Class

On this route, layover flights are cheaper than nonstop options on average. Layover fares average $318 round-trip via Seattle/Tacoma Intl (SEA), compared to $500 for nonstop.

There is no standard. Checked-bag policies vary by airline on this route. Most carriers charge $45–$90 for the first checked bag in economy. Premium fares and elite-status bookings typically include a free checked bag.

The Boeing 737-800 Passenger/BBJ2 (winglets) family is used most often on this route, operated mainly by Southwest. Other aircraft seen on the route include Boeing 737 MAX 8 variants.

One-stop flights from St. Louis to San Diego most commonly connect through:

• Denver Intl (DEN) - 31% of one-stop connections
• Phoenix Sky Harbor Intl (PHX) - 26% of one-stop connections
• Salt Lake City (SLC) - 14% of one-stop connections
• Dallas/Fort Worth (DFW) - 10% of one-stop connections

Denver Intl (DEN) handles the largest share of one-stop connections on this route.

Yes. Being flexible with your travel dates can save you up to 29% on the St. Louis to San Diego route. Wednesday is the cheapest departure day at $336 round-trip on average, while Sunday is the most expensive at $468, a difference of $132. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

Morning is the busiest departure period on St. Louis to San Diego flights, with 100% of flights leaving in that window. Afternoon departures account for 0%, evening flights for 0%, and night flights for 0%.

Some of the most popular sights in San Diego are Gaslamp Quarter, San Diego Convention Center and SeaWorld San Diego. These are among the most viewed places in San Diego on KAYAK.

These are the earliest and latest flight times available from St. Louis to San Diego:

• Earliest: departs at 7:55 am and lands at 11:50 am
• Latest: departs at 10:45 pm and lands at 2:40 am.

The flight takes about 3h 55m.

Last-minute fares on this route - booked within 2 weeks of departure - run 17% above the route average of $398. Book 5 weeks before departure for the lowest fares.

A nonstop flight from St. Louis to San Diego takes 3h 55m, covering 1,553 miles.

No, a passport is not required for this domestic route, but you will need a real ID-compliant driver's license, a state ID, or another TSA-accepted form of identification.

Yes. Based on fares seen in the past 5 days, round-trip prices on this route showed a wide range, from about $281 to $1,589. That means the highest observed fare was about 6x higher than the lowest one.

One-way fares from St. Louis to San Diego are currently lower than usual. Average one-way flight prices are about $150, which is 30% below the typical average for this route.

Flying via Phoenix Sky Harbor Intl (PHX) gives the shortest average 1-stop total travel time at 5h 41m, compared with 5h 52m via Dallas Love Field (DAL) and 6h 03m via Salt Lake City (SLC).

San Diego is 2 hours behind St. Louis (Pacific Time vs Central Time). Plan for the time shift when scheduling connections or first-day activities.

San Diego Airport (SAN) hosts 5 major car rental companies, with daily rates starting from around $14 for economy cars. Top options include:
• Dollar
• Payless
• Europcar
• Thrifty
• Fox

Round-trip flights from St. Louis to San Diego range from $305 to $490, with an average of $398 over the past 12 months. Anything below $305 counts as a good deal.