$213 Cheap Flights from Tri-Cities (TRI) to St. Louis (STL)

View $213 flight on Sun, Dec 21, 2025Opens in a new window

Popular airlines from Tri-Cities, TN (TRI-Tri-Cities Regional) to St. Louis Lambert Intl. Airport (STL)

Cheap Flights from Tri-Cities to St. Louis (TRI-STL)

Prices were available within the past 7 days and start at $213 for one-way flights and $307 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, Jan 6 - Tue, Jan 20
TRI
Tri-Cities
STL
St. Louis
$307 Roundtrip, found 1 day ago
$307
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Jan 6 from Tri-Cities to St. Louis, returning Tue, Jan 20, priced at $307 found 1 day ago
American Airlines
Wed, Dec 10 - Sat, Dec 13
TRI
Tri-Cities
STL
St. Louis
$308 Roundtrip, found 6 days ago
$308
Roundtrip
found 6 days ago
Select American Airlines flight, departing Wed, Dec 10 from Tri-Cities to St. Louis, returning Sat, Dec 13, priced at $308 found 6 days ago
Delta
Wed, Feb 4 - Sat, Feb 7
TRI
Tri-Cities
STL
St. Louis
$308 Roundtrip, found 4 days ago
$308
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Feb 4 from Tri-Cities to St. Louis, returning Sat, Feb 7, priced at $308 found 4 days ago
American Airlines
Wed, Dec 10 - Sat, Dec 13
TRI
Tri-Cities
STL
St. Louis
$313 Roundtrip, found 6 days ago
$313
Roundtrip
found 6 days ago
Select American Airlines flight, departing Wed, Dec 10 from Tri-Cities to St. Louis, returning Sat, Dec 13, priced at $313 found 6 days ago
Delta
Tue, Jan 6 - Mon, Jan 19
TRI
Tri-Cities
STL
St. Louis
$317 Roundtrip, found 1 day ago
$317
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Jan 6 from Tri-Cities to St. Louis, returning Mon, Jan 19, priced at $317 found 1 day ago
American Airlines
Wed, Feb 4 - Sat, Feb 7
TRI
Tri-Cities
STL
St. Louis
$322 Roundtrip, found 4 days ago
$322
Roundtrip
found 4 days ago
Select American Airlines flight, departing Wed, Feb 4 from Tri-Cities to St. Louis, returning Sat, Feb 7, priced at $322 found 4 days ago
American Airlines
Fri, Dec 5 - Sat, Dec 6
TRI
Tri-Cities
STL
St. Louis
$327 Roundtrip, found 21 hours ago
$327
Roundtrip
found 21 hours ago
Select American Airlines flight, departing Fri, Dec 5 from Tri-Cities to St. Louis, returning Sat, Dec 6, priced at $327 found 21 hours ago
American Airlines
Wed, Feb 4 - Sat, Feb 7
TRI
Tri-Cities
STL
St. Louis
$327 Roundtrip, found 4 days ago
$327
Roundtrip
found 4 days ago
Select American Airlines flight, departing Wed, Feb 4 from Tri-Cities to St. Louis, returning Sat, Feb 7, priced at $327 found 4 days ago
American Airlines
Fri, Dec 5 - Sat, Dec 6
TRI
Tri-Cities
STL
St. Louis
$332 Roundtrip, found 21 hours ago
$332
Roundtrip
found 21 hours ago
Select American Airlines flight, departing Fri, Dec 5 from Tri-Cities to St. Louis, returning Sat, Dec 6, priced at $332 found 21 hours ago
American Airlines
Fri, Nov 28 - Mon, Dec 8
TRI
Tri-Cities
STL
St. Louis
$336 Roundtrip, found 3 days ago
$336
Roundtrip
found 3 days ago
Select American Airlines flight, departing Fri, Nov 28 from Tri-Cities to St. Louis, returning Mon, Dec 8, priced at $336 found 3 days 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 $357
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $357

Frequently asked questions

How much does a flight from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL) cost?
Lock in a cheap one-way flight from $213 or cheap return flight from $307 from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight offers on this route.
What is the cheapest month to fly from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL)?
The cheapest month to fly from TRI to STL is January, when demand is low. Off-peak season is typically when airlines offer better prices between these airports.
What is the cheapest airline that flies from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL)?
To find the cheapest airline that'll fly you from TRI to STL, use Expedia's filter tool. Customize your search based on what's important to you, such as preferred carriers and number of stops. You can then sort your results by "Price (lowest to highest)" to see the cheapest flights first.
How many flights per day from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL)?
There aren't any daily direct flights departing from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL). But you can opt for flights with layovers. Filter your search on Expedia to include one or two stops, and you'll be cruising above the clouds in no time.
What day of the week has the most flights from TRI to STL?
You'll generally find Tuesday the quietest day for flights, while Fridays tend to be the busiest.* However this can change from season to season and during peak travel times or public holidays.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL)?
Opt for a flight from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL) that leaves before 3 PM to reduce the risk of delays and cancellations. Later departures have a 22% higher chance of being canceled, on average.**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 Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute fares from TRI to STL are typically more expensive. To secure the lowest prices, start looking for flights well ahead of time. That being said, if you're flexible with your travel dates, you may land a cheap ticket right before your journey.
Is it cheaper to book a TRI to STL flight and hotel package?
Compared with arranging flights and hotels separately, booking a TRI to STL flight and hotel package with Expedia could lead to significant savings. What's more, having everything in one place takes the hassle out of planning your trip. Just secure your flights and choose from our wide range of stays, then customize your trip with extras like activities and car rentals.
Can I cancel or change the date of my flight from Tri-Cities Regional Airport (TRI) to Lambert-St. Louis Intl. Airport (STL)?
If you reserved your TRI to STL flight within the last 24 hours, you may be able to cancel or modify it without fees. Depending on the airline and the type of ticket you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal for more information.

Travel information

Origin airport
Tri-Cities Regional
Destination airport
Lambert-St. Louis Intl.
Airlines serving
American Airlines, Delta
Roundtrip price
$306
Distance
462 mi

Book with confidence

Tri-Cities to St. Louis Flights

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

 

The best time to book a flight from Tri-Cities to St. Louis

Sunday is one of the best days to book for cheap flights from Tri-Cities 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 Tri-Cities 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 Tri-Cities to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $213 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 Tri-Cities 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 Tri-Cities 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.

 

Tri-Cities to St. Louis Flights

Explore a world of travel with Expedia

*Available to One Key members.