$159 Cheap Flights from Santa Rosa (STS) to St. Louis (STL)

View $159 flight on Tue, Sep 16, 2025Opens in a new window

Popular airlines from Santa Rosa, CA (STS-Sonoma County) to St. Louis Lambert Intl. Airport (STL)

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Cheap Flights from Santa Rosa to St. Louis (STS-STL)

Prices were available within the past 7 days and start at $159 for one-way flights and $318 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Wed, Oct 1 - Tue, Oct 7
STS
Santa Rosa
STL
St. Louis
$318 Roundtrip, found 1 day ago
$318
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Wed, Oct 1 from Santa Rosa to St. Louis, returning Tue, Oct 7, priced at $318 found 1 day ago
Hawaiian Airlines
Tue, Sep 30 - Thu, Oct 2
STS
Santa Rosa
STL
St. Louis
$332 Roundtrip, found 4 days ago
$332
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Tue, Sep 30 from Santa Rosa to St. Louis, returning Thu, Oct 2, priced at $332 found 4 days ago
Hawaiian Airlines
Fri, Oct 3 - Tue, Oct 7
STS
Santa Rosa
STL
St. Louis
$332 Roundtrip, found 4 days ago
$332
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Fri, Oct 3 from Santa Rosa to St. Louis, returning Tue, Oct 7, priced at $332 found 4 days ago
Hawaiian Airlines
Tue, Sep 30 - Fri, Oct 3
STS
Santa Rosa
STL
St. Louis
$338 Roundtrip, found 4 days ago
$338
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Tue, Sep 30 from Santa Rosa to St. Louis, returning Fri, Oct 3, priced at $338 found 4 days ago
Hawaiian Airlines
Thu, Oct 2 - Mon, Oct 6
STS
Santa Rosa
STL
St. Louis
$346 Roundtrip, found 4 days ago
$346
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Thu, Oct 2 from Santa Rosa to St. Louis, returning Mon, Oct 6, priced at $346 found 4 days ago
Hawaiian Airlines
Fri, Oct 3 - Mon, Oct 6
STS
Santa Rosa
STL
St. Louis
$346 Roundtrip, found 4 days ago
$346
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Fri, Oct 3 from Santa Rosa to St. Louis, returning Mon, Oct 6, priced at $346 found 4 days ago
Hawaiian Airlines
Tue, Sep 30 - Fri, Oct 3
STS
Santa Rosa
STL
St. Louis
$350 Roundtrip, found 4 days ago
$350
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Tue, Sep 30 from Santa Rosa to St. Louis, returning Fri, Oct 3, priced at $350 found 4 days ago
Hawaiian Airlines
Tue, Sep 23 - Wed, Oct 1
STS
Santa Rosa
STL
St. Louis
$356 Roundtrip, found 1 day ago
$356
Roundtrip
found 1 day ago
Select Hawaiian Airlines flight, departing Tue, Sep 23 from Santa Rosa to St. Louis, returning Wed, Oct 1, priced at $356 found 1 day ago
Hawaiian Airlines
Mon, Oct 6 - Sat, Oct 11
STS
Santa Rosa
STL
St. Louis
$358 Roundtrip, found 4 days ago
$358
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Mon, Oct 6 from Santa Rosa to St. Louis, returning Sat, Oct 11, priced at $358 found 4 days ago
American Airlines
Fri, Oct 10 - Tue, Oct 14
STS
Santa Rosa
STL
St. Louis
$564 Roundtrip, found 7 hours ago
$564
Roundtrip
found 7 hours ago
Select American Airlines flight, departing Fri, Oct 10 from Santa Rosa to St. Louis, returning Tue, Oct 14, priced at $564 found 7 hours 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 $475
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $475
Flights from Santa Rosa (STS) to St. Louis (STL)
Origin airport
Sonoma County
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines
Roundtrip price
$318
Distance
1741 mi

Santa Rosa to St. Louis Flights

The cheapest times to fly from Santa Rosa 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 Santa Rosa to St. Louis are during the month of October. You can find some of the cheapest flights from Santa Rosa to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Santa Rosa to St. Louis

Sunday is one of the best days to book for cheap flights from Santa Rosa 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 Santa Rosa 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 Santa Rosa to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $159 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 Santa Rosa 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 Santa Rosa 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 Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL) cost?
Grab a cheap one-way flight from $159 or cheap return flight from $318 from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight offers on this route.
What is the cheapest month to fly from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL)?
October is the least expensive month to fly from STS to STL. Planning your trip for the off-season is often the key to finding better deals on flights.
What is the cheapest airline that flies from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL)?
Expedia's filter tool lets you easily compare different airlines, travel time and fares all in one place. Customize the search to your preferences, then sort by "Price (lowest to highest)" to find the carrier with the cheapest STS to STL flight.
How many flights per day from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL)?
Nonstop flights from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL) aren't available daily, so you'll need to take a flight with a layover. Explore your options with Expedia's filter tool. Enter your dates and click on either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STS to STL?
Typically you'll find the greatest selection of flight options on a Friday. Tuesdays tend to be the quietest.* But this can vary depending on the time of year, carrier and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL)?
Opt for a flight from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL) that leaves before 3 PM to reduce the risk of cancellations. Departures later than this are on average 22% more likely to be canceled.**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.
Is it cheaper to buy a plane ticket from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute bookings from STS to STL are generally more expensive. To lock in the lowest prices, start searching for flights ahead of time. That said, if your travel plans are flexible, it's possible to find a cheap fare just before your departure.
Is it cheaper to book a STS to STL flight and hotel package?
You'll generally save money by securing a STS to STL flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's easy to manage it all in one place. Once you've chosen your ideal accommodations and flights, you can add extras such as activities, tours and car rentals.
Can I cancel or change the date of my flight from Sonoma County Airport (STS) to Lambert-St. Louis Intl. Airport (STL)?
If you booked your STS to STL flight in the last 24 hours, you may be able to cancel or modify it at no cost. Depending on the airline and the type of ticket you purchased, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal for more details.

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*Available to One Key members.