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$104 Cheap Flights from San Diego (SAN) to St. Louis (STL)

View $104 flight on Thu, Oct 29, 2026Opens 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 $104 for one-way flights and $208 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Fri, Sep 18 - Mon, Sep 21
SAN
San Diego
STL
St. Louis
$208 Roundtrip, just found
$208
Roundtrip
just found
Select Frontier Airlines flight, departing Fri, Sep 18 from San Diego to St. Louis, returning Mon, Sep 21, priced at $208 just found
Frontier Airlines
Sun, Sep 6 - Fri, Sep 18
SAN
San Diego
STL
St. Louis
$218 Roundtrip, found 1 hour ago
$218
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Sun, Sep 6 from San Diego to St. Louis, returning Fri, Sep 18, priced at $218 found 1 hour ago
Alaska Airlines
Fri, Sep 11 - Wed, Sep 16
SAN
San Diego
STL
St. Louis
$232 Roundtrip, found 3 days ago
$232
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Fri, Sep 11 from San Diego to St. Louis, returning Wed, Sep 16, priced at $232 found 3 days ago
Delta
Wed, Oct 21 - Thu, Oct 29
SAN
San Diego
STL
St. Louis
$233 Roundtrip, found 4 days ago
$233
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Oct 21 from San Diego to St. Louis, returning Thu, Oct 29, priced at $233 found 4 days ago
Alaska Airlines
Fri, Sep 11 - Wed, Sep 16
SAN
San Diego
STL
St. Louis
$237 Roundtrip, found 3 days ago
$237
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Fri, Sep 11 from San Diego to St. Louis, returning Wed, Sep 16, priced at $237 found 3 days ago
Frontier Airlines
Fri, Sep 18 - Mon, Sep 21
SAN
San Diego
STL
St. Louis
$238 Roundtrip, just found
$238
Roundtrip
just found
Select Frontier Airlines flight, departing Fri, Sep 18 from San Diego to St. Louis, returning Mon, Sep 21, priced at $238 just found
Frontier Airlines
Thu, Sep 24 - Mon, Sep 28
SAN
San Diego
STL
St. Louis
$248 Roundtrip, just found
$248
Roundtrip
just found
Select Frontier Airlines flight, departing Thu, Sep 24 from San Diego to St. Louis, returning Mon, Sep 28, priced at $248 just found
American Airlines
Fri, Sep 18 - Mon, Sep 21
SAN
San Diego
STL
St. Louis
$258 Roundtrip, just found
$258
Roundtrip
just found
Select American Airlines flight, departing Fri, Sep 18 from San Diego to St. Louis, returning Mon, Sep 21, priced at $258 just found
American Airlines
Thu, Oct 15 - Mon, Oct 19
SAN
San Diego
STL
St. Louis
$263 Roundtrip, found 2 hours ago
$263
Roundtrip
found 2 hours ago
Select American Airlines flight, departing Thu, Oct 15 from San Diego to St. Louis, returning Mon, Oct 19, priced at $263 found 2 hours ago
Southwest Airlines
Fri, Oct 16 - Mon, Oct 19
SAN
San Diego
STL
St. Louis
$281 Roundtrip, found 1 hour ago
$281
Roundtrip
found 1 hour ago
Select Southwest Airlines flight, departing Fri, Oct 16 from San Diego to St. Louis, returning Mon, Oct 19, priced at $281 found 1 hour ago

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 $302
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $302

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

September is typically the cheapest month to fly

From $136 - $263 per traveler.

What you need to know for your flight from San Diego Intl. to Lambert-St. Louis Intl.

San Diego (SAN) to St. Louis (STL) at a glance

Travel from San Diego International Airport (SAN) to Lambert-St. Louis International Airport (STL) with a variety of airlines offering flights on this domestic short-haul route. Whether you're searching for budget-friendly options or full-service experiences, you can easily compare choices to find the best itinerary that meets your budget and schedule. Discover the sights and neighborhoods of St. Louis as you plan your journey with convenient flight options available from San Diego to St. Louis.

  • Fastest flight duration: around 3h 30m non-stop
  • Route distance: roughly 1,600 miles (2,570 km)
  • Flights per week: around 25+ flights with multiple daily departures on average
  • Typical fares (one-way): economy tickets often range from $100–$465, depending on seasonality and how far ahead you book

Flights from San Diego International Airport (SAN) to Lambert-St. Louis International Airport (STL)

Based on the latest traveler bookings, here are the top airlines favored for flights from San Diego to St. Louis, featuring both one-stop and non-stop options. Common layover points include Sky Harbor International Airport in Phoenix (PHX) with a 1-hour layover, Dallas-Fort Worth International Airport (DFW) offering approximately 1 hour and 15 minutes, and Denver International Airport (DEN), also with a 1 hour and 15 minutes layover. This variety allows you to balance price, total travel time, and cabin class to craft your ideal itinerary.

  • Southwest Airlines: This budget-friendly airline provides both non-stop and one-stop flights, with one-way ticket prices generally falling between $120 and $545. Southwest operates around 35% of the flights on this route, and you can expect a non-stop travel duration of about 3 hours and 30 minutes.
  • American Airlines: As a full-service airline, American offers one-stop flights with one-way fares typically ranging from $115 to $410. It accounts for approximately 33% of the departures on this route, featuring an in-flight duration of 4 hours and 45 minutes, totaling around 6 hours and 15 minutes when including layovers.
  • Delta: This full-service airline provides one-stop service, with one-way fares usually between $130 and $400. Delta represents about 13% of the departures on this route, with an in-flight time of 4 hours and 45 minutes, and an overall travel time of roughly 6 hours and 15 minutes, factoring in layovers.
  • United: United Airlines is another full-service option that features one-stop flights, with one-way fares typically from $130 to $445. This airline makes up around 11% of the departures on this route, with a flight duration of 4 hours and 45 minutes and a total journey time of about 6 hours and 15 minutes, including layovers.
  • Frontier Airlines: As a low-cost carrier, Frontier offers one-stop service with one-way fares generally ranging from $100 to $240. They account for approximately 7% of departures on this route, and the in-flight time is about 4 hours and 45 minutes, with a total travel duration of roughly 6 hours and 15 minutes, including layovers.

Travelers flying from San Diego to St. Louis can enhance their experience by upgrading to first class, with options available through both American Airlines and United Airlines for this route.

Best time to fly from San Diego (SAN) to St. Louis (STL)

The most popular months for travelers flying from San Diego to St. Louis are January, March, and April, when peak temperatures in St. Louis reach up to 56.1°F in April. If you prefer quieter travel, consider August, the least busy and relatively cheaper time to visit with fewer crowds and temperatures around 77°F. For better deals, May usually offers the lowest average one-way fare around $207. Flight availability peaks in May, with approximately 31 flights per week, making it easier to find convenient departure times. February has the fewest flights, with approximately 18 flights per week.

  • Cheapest time to fly: May usually offers good deals with average one-way fare around $207, roughly 14% cheaper than the yearly average.
  • More budget-friendly months to fly: September and April typically offer average one-way fares of around $224.
  • Most flight options: May has the highest number of flights from San Diego to St. Louis, with approximately 31 flights per week, giving you more flexibility in scheduling your trip.
calendar iconMonthtemperature iconTemperaturecrowd level iconDemandflights iconWeekly Flightsprice iconAverage one-way Fare
January31.6°F (-0.2°C)Moderately High19$228
February34.9°F (1.6°C)Average18$233
March46.4°F (8.0°C)Moderately High25$265
April56.1°F (13.4°C)Moderately High29$227
May66.6°F (19.2°C)Average31$207
June76.1°F (24.5°C)Average29$252
July78.6°F (25.9°C)Average27$262
August77.0°F (25.0°C)Moderately Low26$242
September70.9°F (21.6°C)Average27$222
October58.6°F (14.8°C)Average25$234
November46.2°F (7.9°C)Moderately Low24$256
December37.8°F (3.2°C)Moderately Low23$273

*Average one-way fare is based on Expedia flight booking data from January 2025 to April 2026 for the specified route and travel class and may change depending on availability, dates, and demand.

Alternative routes from San Diego (SAN) to St. Louis (STL)

  • San Diego to St. Louis (SAN-SUS): The Spirit of St. Louis Airport (SUS) is located approximately 16 miles from Lambert-St. Louis International Airport (STL).
  • San Diego to St. Louis (SAN-CPS): St. Louis Downtown Airport (CPS) is around 16 miles distant from Lambert-St. Louis International Airport (STL).
  • San Diego to Springfield (SAN-SPI): Abraham Lincoln Capital Airport (SPI) lies about 85 miles away from Lambert-St. Louis International Airport (STL).

How to find the best prices for flights from San Diego (SAN) to St. Louis (STL)

Getting some of the best deals on flights from San Diego to St. Louis is all about timing and flexibility. Here are some key tips to help you save:

  1. Best times to book and fly: cheaper fares are usually found when booking 2-8 weeks in advance, which coincides with when most travelers make their reservations. Evening departures (6 pm-12 am) tend to be less expensive, although morning flights (5 am-12 pm) are the most popular. Additionally, flying on Thursday typically offers lower prices, while Friday remains the busiest travel day.
  2. Set up price alerts: stay updated on price changes by using Expedia's Price Tracker. Receive alerts when fares drop for your selected route.
  3. Bundle and save: bundle your flight and hotel to save on Expedia, or unlock a hotel deal after booking your flight.*
  4. Compare flight options: use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
  5. Stay flexible with dates: being open to different travel days can sometimes help you find better prices on flights and hotels.
  6. Think about luggage: nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your allowance before confirming your booking to avoid excess baggage fees at the airport.

*Members only. Savings vary and are not available on all bundles. Select hotels.

Arriving at Lambert-St. Louis International Airport from San Diego International Airport

St. Louis welcomes travelers from San Diego with a range of transport options based on price, convenience, and proximity. Here's how to reach St. Louis efficiently:

  • Hotel transfer: Transfers offer a convenient way to reach your hotel in St. Louis, with private rides that can be arranged in advance.
  • Car rental: Renting a car from Lambert-St. Louis International Airport is a great option if you plan to explore and sightsee beyond the city. Browse cheap car rentals at Lambert-St. Louis International Airport on Expedia.
  • Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.
  • Public transportation: From Lambert-St. Louis International Airport, the Lambert Main Terminal Station, a metro station, is conveniently located just 0.1 miles away on foot, providing easy access to public transport.

Frequently asked questions

How much does a flight from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) cost?
You can find cheap one-way flights from $104 and cheap return flights from $208 San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) with Expedia. One-way flights usually range from $186 to $1319, and return flights typically cost between $360 and $1248. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) ticket fares go up or down.*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.
What is the cheapest month to fly from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The cheapest month to fly from SAN to STL is September when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you're able to. Use the calendar view in your search to see which months have low fares on this route.
Which airlines fly direct from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Enter SAN to STL and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
What is the cheapest airline that flies from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Southwest Airlines is one of the cheapest airlines offering nonstop flights from San Diego, CA (SAN) to St. Louis, MO (STL), with round-trip tickets starting from around $263. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
To find a cheap flight from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best airline to fly with from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) will differ from traveler to traveler. If you like to fly early, WN offers early morning flights. If price is the most important factor, WN typically offers the lowest fares. Alaska Airlines offers the most daily flights from SAN to STL, which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
How many flights per day from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
You can find approximately 1 nonstop flights per day from San Diego Intl. (SAN) to Lambert-St. Louis Intl. (STL). For more options, look at flights that include layovers.
What is the earliest flight from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The earliest flight from San Diego International Airport (SAN) to St. Louis (STL) typically departs at around 6:00 AM, operated by American Airlines. An early departure like this allows you to make the most of your day upon arrival. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What are the most popular departure times for flights from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The most popular departure times for flights from San Diego, CA (SAN) to St. Louis, MO (STL) are in the early morning, from 6am to 9am. About 35% of passengers prefer this time window. Many major carriers, including American Airlines, Southwest Airlines and United Airlines, offer flights during this window. This timing works well because it lets you arrive in St. Louis with a full day ahead of you.
How long does it take to fly from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Flying nonstop from SAN to STL takes around 3 hours 30 minutes, with the route covering approximately 1,555 miles. Flights with a layover typically take 5 hours longer than direct options. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Select the "Business class" and "First class" filters when looking for SAN to STL flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight with Expedia?
It's easy to earn miles on a San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for St. Louis from San Diego Intl. (SAN)?
From San Diego Intl. (SAN), you can fly into Lambert-St. Louis Intl. (STL) to reach St. Louis. Some flights may connect through major hubs like Harry Reid Intl. (LAS), Sky Harbor Intl. (PHX), Los Angeles Intl. (LAX) before reaching St. Louis. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) at the last minute?
Typically, booking a last minute flight from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight and hotel package?
Securing a San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) St Louis Vacation Packages is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
If you booked your San Diego, CA (SAN-San Diego Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

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
$208
Distance
1554 mi
Average flight time
7 hours 35 mins

Book with confidence

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 September. 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 2026. You can also book with separate airlines for your outbound and return journeys, from $104 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.

 

San Diego to St. Louis Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

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