$114 Cheap Flights from San Diego (SAN) to St. Louis (STL)

View $114 flight on Sat, Sep 27, 2025Opens in a new window

Popular airlines from San Diego Intl. Airport (SAN) to St. Louis Lambert Intl. Airport (STL)

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Cheap Flights from San Diego to St. Louis (SAN-STL)

Prices were available within the past 7 days and start at $114 for one-way flights and $228 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Sat, Oct 4 - Wed, Oct 8
SAN
San Diego
STL
St. Louis
$228 Roundtrip, found 9 hours ago
$228
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Sat, Oct 4 from San Diego to St. Louis, returning Wed, Oct 8, priced at $228 found 9 hours ago
American Airlines
Wed, Oct 1 - Wed, Oct 8
SAN
San Diego
STL
St. Louis
$229 Roundtrip, found 1 hour ago
$229
Roundtrip
found 1 hour ago
Select American Airlines flight, departing Wed, Oct 1 from San Diego to St. Louis, returning Wed, Oct 8, priced at $229 found 1 hour ago
Frontier Airlines
Thu, Oct 9 - Tue, Oct 14
SAN
San Diego
STL
St. Louis
$238 Roundtrip, found 3 hours ago
$238
Roundtrip
found 3 hours ago
Select Frontier Airlines flight, departing Thu, Oct 9 from San Diego to St. Louis, returning Tue, Oct 14, priced at $238 found 3 hours ago
American Airlines
Sat, Oct 4 - Sun, Oct 12
SAN
San Diego
STL
St. Louis
$239 Roundtrip, found 16 hours ago
$239
Roundtrip
found 16 hours ago
Select American Airlines flight, departing Sat, Oct 4 from San Diego to St. Louis, returning Sun, Oct 12, priced at $239 found 16 hours ago
American Airlines
Mon, Sep 1 - Tue, Sep 9
SAN
San Diego
STL
St. Louis
$244 Roundtrip, found 1 day ago
$244
Roundtrip
found 1 day ago
Select American Airlines flight, departing Mon, Sep 1 from San Diego to St. Louis, returning Tue, Sep 9, priced at $244 found 1 day ago
Frontier Airlines
Mon, Sep 1 - Tue, Sep 9
SAN
San Diego
STL
St. Louis
$246 Roundtrip, found 1 day ago
$246
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Mon, Sep 1 from San Diego to St. Louis, returning Tue, Sep 9, priced at $246 found 1 day ago
Frontier Airlines
Thu, Sep 4 - Sun, Sep 7
SAN
San Diego
STL
St. Louis
$248 Roundtrip, just found
$248
Roundtrip
just found
Select Frontier Airlines flight, departing Thu, Sep 4 from San Diego to St. Louis, returning Sun, Sep 7, priced at $248 just found
Southwest Airlines
Mon, Dec 8 - Tue, Dec 9
SAN
San Diego
STL
St. Louis
$254 Roundtrip, found 13 hours ago
$254
Roundtrip
found 13 hours ago
Select Southwest Airlines flight, departing Mon, Dec 8 from San Diego to St. Louis, returning Tue, Dec 9, priced at $254 found 13 hours ago
Alaska Airlines
Wed, Oct 1 - Wed, Oct 8
SAN
San Diego
STL
St. Louis
$254 Roundtrip, found 1 hour ago
$254
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Wed, Oct 1 from San Diego to St. Louis, returning Wed, Oct 8, priced at $254 found 1 hour ago
United
Thu, Dec 4 - Sat, Dec 6
SAN
San Diego
STL
St. Louis
$259 Roundtrip, found 5 days ago
$259
Roundtrip
found 5 days ago
Select United flight, departing Thu, Dec 4 from San Diego to St. Louis, returning Sat, Dec 6, priced at $259 found 5 days ago

Find the cheapest month to fly from San Diego (SAN) to St. Louis (STL)

October is typically the cheapest month to fly

From $118 - $315 per traveler.

Graph displaying average flight prices per month

Alternative airports near St. Louis

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $477
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $477
Flights from San Diego (SAN) to St. Louis (STL)
Origin airport
San Diego Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$228
Distance
1554 mi
Average flight time
5 hours 58 mins

San Diego to St. Louis Flights

The cheapest times to fly from San Diego to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from San Diego to St. Louis are during the month of October. You can find some of the cheapest flights from San Diego to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from San Diego to St. Louis

Sunday is one of the best days to book for cheap flights from San Diego to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from San Diego to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from San Diego to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $114 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap San Diego to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your San Diego to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL) cost?
Cheap return fares from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL) start from $296. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving SAN on August 15 2025 and touching down at STL. The price was last updated on July 23 2025 and has not changed since.
What is the cheapest month to fly from SAN to STL?
The cheapest flights from SAN to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
Fly directly from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL) on a Southwest Airlines flight.
What is the cheapest airline that flies from SAN to STL?
Book a flight from SAN to STL with Southwest Airlines. This carrier currently offers the lowest one-way fare for this route, starting at $140. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from SAN on October 18 2025. Prices were last updated on July 23 2025 and have not changed since.
How many flights per day from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
On average, San Diego Intl. Airport (SAN) only offers 1 direct flight to Lambert-St. Louis Intl. Airport (STL) each day. To explore more options, try Expedia's easy-to-use filters. Simply enter your details, then choose "1 Stop" or "2+ Stops" to find flights offering layovers.
What are the most popular departure times for flights from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
Flights between SAN and STL tend to be busiest at 9 AM. If you want a quieter experience and potentially cheaper prices, choose a departure outside the usual busy windows.
What day of the week has the most flights from SAN to STL?
Sunday offers the most flights from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL). Consider taking off on this day and you'll have the best chance of finding a departure that fits your itinerary.
What is the earliest flight from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
San Diego Intl. Airport (SAN)'s earliest flight to Lambert-St. Louis Intl. Airport (STL) leaves at approximately 6:50AM UTC-8. With a travel duration of 3h 25m, you'll touch down at around 12:15PM UTC-6.
How long does it take to fly from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
The average flight time from SAN to STL is 3 hours and 26 minutes, covering a total distance of 1,550 mi.
What airline has the least delays from SAN to STL?
Alaska Airlines has the strongest track record for on-time direct flights from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL), with an on-time score of 82%. Use the Expedia App to look up your flight schedule before you leave and get notified of any changes.
What is the best time to fly from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
To touch down at Lambert-St. Louis Intl. Airport (STL) without delays, book a flight that leaves from San Diego Intl. Airport (SAN) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for St. Louis from San Diego Intl. Airport (SAN)?
If you've booked a direct flight from San Diego Intl. Airport (SAN) to St. Louis, Lambert-St. Louis Intl. Airport (STL) is the only airport you can touch down at.
Is it cheaper to buy a plane ticket from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute bookings from SAN to STL are typically more expensive. To lock in the lowest rates, start looking for flights ahead of time. That being said, if your travel plans are flexible, you may find a cheap ticket just before your departure.
Is it cheaper to book a SAN to STL flight and hotel package?
Compared with arranging flights and hotels separately, booking a SAN to STL flight and hotel package with Expedia could result in significant savings. What's more, managing everything in one place will take the stress out of planning your trip. Simply pick your flights and select from our wide range of hotels, then tailor your trip with extras like activities, tours and car rentals.
Can I cancel or change the date of my flight from San Diego Intl. Airport (SAN) to Lambert-St. Louis Intl. Airport (STL)?
In most cases, you can modify or cancel your SAN to STL flight. However, additional charges may apply, especially if you made your booking over 24 hours ago. Double-check your itinerary for the airline's fees and policies on flight changes, or if you'd like more details, head to our Customer Service portal.

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