San Diego

$93+ Cheap flights from St. Louis to San Diego (STL - SAN)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SAN
Aug 2 — Aug 91
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Cheapflights Tip: The best prices from Lambert-St Louis to San Diego are usually found in January or October, booked 78 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from St. Louis to San Diego

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to San Diego (SAN). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 28, 2025.

Round-trip from

$225
(FlightHub)

One-way from

$93
(Trip.com)

Popular in

March

Cheapest in

January

Average price

$352

Good round-trip deal

$317 or less

Good one-way deal

$174 or less
From Lambert-St Louis to San Diego
One-way flight from Lambert-St Louis to San Diego
Highest demand for flights based on searches. 6% potential increase in price ($24 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($11 potential savings vs. average RT price).
Average for round-trip flights in July 2025
Price to beat on a round-trip flight from Lambert-St Louis to San Diego.
Price to beat on a one-way flight from Lambert-St Louis to San Diego.

Find flight deals from St. Louis to San Diego

Cheapest flights from St. Louis to San Diego
Explore the most affordable flight options available from St. Louis to San Diego. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 28, 2025.

This FlightHub deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/227:52 pmSTL - SAN
1 stop5h 58mFrontier
Sat 10/256:25 amSAN - STL
1 stop24h 42mFrontier
Deal found 7/27$225
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/308:25 amSTL - SAN
Nonstop3h 50mSouthwest
Wed 9/31:25 pmSAN - STL
1 stop7h 10mSouthwest
Deal found 7/25$286
This Mytrip deal was found by Cheapflights users on 7/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/282:30 pmSTL - SAN
2 stops11h 07mSpirit Airlines
Sat 8/301:17 pmSAN - STL
2 stops22h 15mSpirit Airlines
Deal found 7/28$294
This United Airlines deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/44:50 pmSTL - SAN
1 stop5h 35mUnited Airlines
Tue 10/711:08 amSAN - STL
2 stops8h 52mUnited Airlines
Deal found 7/26$324
This Alaska Airlines deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/226:33 amSTL - SAN
1 stop9h 24mAlaska Airlines
Sat 10/258:41 amSAN - STL
2 stops13h 22mAlaska Airlines
Deal found 7/26$337
This Mytrip deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/172:30 pmSTL - SAN
2 stops18h 51mMultiple Airlines
Thu 8/215:36 pmSAN - STL
1 stop16h 08mMultiple Airlines
Deal found 7/27$338

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to San Diego that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 28, 2025.
Use the filters below to find and compare flights from St. Louis to San Diego that are best for you.

Fly from

St. Louis

Fly to

San Diego

Route

Depart

Return

Price

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Wed 10/22

7:52 pm-11:50 pm

1 stop5h 58m

San Diego

Sat 10/25

6:25 am-9:07 am

1 stop24h 42m

$225

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Sat 8/30

8:25 am-10:15 am

Nonstop3h 50m

San Diego

Wed 9/3

1:25 pm-10:35 pm

1 stop7h 10m

$286

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Thu 8/28

2:30 pm-11:37 pm

2 stops11h 07m

San Diego

Sat 8/30

1:17 pm-1:32 pm

2 stops22h 15m

$294

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Sat 10/4

4:50 pm-8:25 pm

1 stop5h 35m

San Diego

Tue 10/7

11:08 am-10:00 pm

2 stops8h 52m

$324

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Wed 10/22

6:33 am-1:57 pm

1 stop9h 24m

San Diego

Sat 10/25

8:41 am-12:03 am

2 stops13h 22m

$337

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Sun 8/17

2:30 pm-7:21 am

2 stops18h 51m

San Diego

Thu 8/21

5:36 pm-11:44 am

1 stop16h 08m

$338

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Thu 9/11

10:49 am-5:42 pm

1 stop8h 53m

$93

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Sat 10/25

6:00 am-2:11 pm

1 stop10h 11m

$114

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Thu 10/2

12:05 pm-11:24 pm

2 stops13h 19m

$124

St. LouisSan Diego

STL - SAN

STLSAN

Lambert-St Louis

Tue 8/26

4:45 pm-6:30 pm

Nonstop3h 45m

$150

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/26

Showing 1-10 of 14 results
1
2

Best time to book a flight from St. Louis to San Diego

Have a flexible travel schedule? Discover the best time to fly to San Diego from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to San Diego

How far ahead should I book a flight from St. Louis to San Diego?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to San Diego. Price data was last updated on July 25, 2025.

To ensure you get the cheapest price possible for a flight from St. Louis to San Diego, you should look to book at least 78 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from St. Louis to San Diego?

Currently, August is the cheapest month in which you can book a flight from St. Louis to San Diego (average of $286). Flying from St. Louis to San Diego in March is currently the most expensive (average of $366). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to SAN?

Find hourly flight availability from St. Louis to San Diego. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 28, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 13% on flights from St. Louis to San Diego by exploring options for tickets in the afternoon.

What is the cheapest day to fly from St. Louis to San Diego?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to San Diego. Price data was last updated on July 27, 2025.

Travelers seeking maximum savings on their St. Louis to San Diego flight should consider departing on Sunday at noon when fares are most often at their lowest. Saturday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

What’s the top layover airport for flights from St. Louis to San Diego?

Share of 1-stop round-trip flights from St. Louis to San Diego chosen by Cheapflights users in the past 12 months, using the same layover each way.

Denver (DEN) – chosen by Cheapflights users on 75% of 1-stop itineraries from St. Louis to San Diego on Cheapflights.

What’s the cheapest layover airport for flights from St. Louis to San Diego?

Average round-trip fare for 1-stop flights from St. Louis to San Diego, chosen by Cheapflights users in the past 12 months, with the same layover each way.

Houston (IAH) is the most affordable 1-stop option, with an average round-trip price of $276.

What’s the fastest layover option from St. Louis to San Diego?

Shortest average travel time for 1-stop one-way flights from St. Louis to San Diego, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Houston (IAH) have the shortest average one-way travel time for 1-stop routes: 4h 27m.

Which airport typically offers the quickest layover for flights from St. Louis to San Diego?

Average layover duration for 1-stop one-way flights from St. Louis to San Diego, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Houston (IAH) offer the fastest connection on this route, with an average layover time of 1h 03m.

Reviews of airlines servicing San Diego

Get insights into the airlines that provide service to San Diego. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to San Diego. Reviews last updated July 28, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest, and Delta from St. Louis to San Diego to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Boarding

8.1

Food

7.1

Comfort

7.8

Crew

8.5

Entertainment

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Food

7.1

Comfort

7.8

Crew

8.5

Entertainment

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Food

7.1

Comfort

7.8

Crew

8.5

Entertainment

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
8.0
Very good

Boarding

8.1

Food

7.1

Comfort

7.8

Crew

8.5

Entertainment

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Food

7.1

Comfort

7.8

Crew

8.5

Entertainment

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Food

7.1

Comfort

7.8

Crew

8.5

Entertainment

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to San Diego. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What airports do I use to fly from St. Louis to San Diego?

    If you book a flight from St. Louis to San Diego, you will be flying from Lambert-St Louis to San Diego. Flights to San Diego (SAN) from Lambert-St Louis (STL) take 3h 45m for a nonstop flight. There is 1 flight from Lambert-St Louis to San Diego per day from 5 airlines.

  • What are the cheapest airlines flying from St. Louis to San Diego round-trip?

    Flying on Frontier is currently your cheapest option to San Diego, with prices starting at $225. Additional round-trip tickets that might be worth considering are offered by Southwest and Spirit Airlines, with the lowest prices starting at $286 and $294, respectively. You may be able to fly from St. Louis to San Diego for 36% less than the average price by searching for these airlines.

  • What are the cheapest airlines to fly from St. Louis to San Diego one-way?

    The cheapest airlines for a one-way flight from St. Louis to San Diego are Frontier ($93), American Airlines ($114), and Spirit Airlines ($124).

  • What are the cheapest flights from St. Louis to San Diego?

    Looking for the cheapest flight from St. Louis to San Diego? While on average our users pay $330, our data indicates the cheapest price to be $169. The most popular route (Lambert-St Louis - San Diego), is priced around $238.

  • Where are the most common layover locations when flying from St. Louis to San Diego?

  • What are some popular things to do or see while on a layover in Denver?

    The majority of Denver visitors spend their time at Coors Field, 16th Street Mall, and Paramount Theatre. Travelers on a layover in Denver can visit Coors Field, 16th Street Mall, and Paramount Theatre, by traveling 18.4 mi, 18.7 mi, and 18.6 mi, respectively after landing at Denver Intl. Travelers can rent a car at Denver Intl for an average daily rate of $64 to make sightseeing during their layover a little easier.

  • Where are the least popular layover locations for St. Louis to San Diego flights?

  • Can I find deals for flights from St. Louis to San Diego that include hotel bookings?

    Yes. In addition to deals on St. Louis to San Diego flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to San Diego?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to San Diego.

  • Can I find deals for business class flights from St. Louis to San Diego?

    Yes. Cheapflights offers flight deals from St. Louis to San Diego by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to San Diego?

    Currently, August is the cheapest month in which you can book a flight from St. Louis to San Diego (average of $286). Flying from St. Louis to San Diego in March is currently the most expensive (average of $366). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near San Diego?

Book flights to San Diego if you plan to visit one of these locations
El Cajon
Chula Vista
Coronado
Poway
National City
Lemon Grove
Imperial Beach
La Mesa
Alpine
Santee

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Alternative routes for St. Louis to San Diego

See prices for flight routes from nearby airports that may be better suited for you.

Top 5 airlines flying from St. Louis to San Diego

Discover the top 5 airlines that operate flights from St. Louis to San Diego. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$108Average$211FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$236Average$305FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$256Average$358FlexibilityNo cancel feeOn-time69%
DeltaCheapest$256Average$305FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$315Average$486FlexibilityNo cancel feeOn-time63%

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