$557 Cheap Flights from St. Louis (STL) to Chiang Mai (CNX)

View $557 flight on Sun, Oct 26, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX)

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Cheap Flights from St. Louis to Chiang Mai (STL-CNX)

Prices were available within the past 7 days and start at $557 for one-way flights and $978 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Thu, Jan 22 - Tue, Feb 3
STL
St. Louis
CNX
Chiang Mai
$978 Roundtrip, found 1 day ago
$978
Roundtrip
found 1 day ago
Select Delta flight, departing Thu, Jan 22 from St. Louis to Chiang Mai, returning Tue, Feb 3, priced at $978 found 1 day ago
Delta
Sun, Jan 25 - Tue, Feb 3
STL
St. Louis
CNX
Chiang Mai
$1,018 Roundtrip, found 1 day ago
$1,018
Roundtrip
found 1 day ago
Select Delta flight, departing Sun, Jan 25 from St. Louis to Chiang Mai, returning Tue, Feb 3, priced at $1,018 found 1 day ago
Delta
Fri, Jan 23 - Tue, Feb 3
STL
St. Louis
CNX
Chiang Mai
$1,024 Roundtrip, found 1 day ago
$1,024
Roundtrip
found 1 day ago
Select Delta flight, departing Fri, Jan 23 from St. Louis to Chiang Mai, returning Tue, Feb 3, priced at $1,024 found 1 day ago
Southwest Airlines
Wed, Apr 22 - Wed, Apr 29
STL
St. Louis
CNX
Chiang Mai
$1,048 Roundtrip, found 13 hours ago
$1,048
Roundtrip
found 13 hours ago
Select Southwest Airlines flight, departing Wed, Apr 22 from St. Louis to Chiang Mai, returning Wed, Apr 29, priced at $1,048 found 13 hours ago
Southwest Airlines
Wed, Apr 8 - Wed, Apr 15
STL
St. Louis
CNX
Chiang Mai
$1,050 Roundtrip, found 19 hours ago
$1,050
Roundtrip
found 19 hours ago
Select Southwest Airlines flight, departing Wed, Apr 8 from St. Louis to Chiang Mai, returning Wed, Apr 15, priced at $1,050 found 19 hours ago
Southwest Airlines
Wed, Apr 22 - Wed, Apr 29
STL
St. Louis
CNX
Chiang Mai
$1,056 Roundtrip, found 13 hours ago
$1,056
Roundtrip
found 13 hours ago
Select Southwest Airlines flight, departing Wed, Apr 22 from St. Louis to Chiang Mai, returning Wed, Apr 29, priced at $1,056 found 13 hours ago
Southwest Airlines
Wed, Apr 22 - Wed, Apr 29
STL
St. Louis
CNX
Chiang Mai
$1,056 Roundtrip, found 6 days ago
$1,056
Roundtrip
found 6 days ago
Select Southwest Airlines flight, departing Wed, Apr 22 from St. Louis to Chiang Mai, returning Wed, Apr 29, priced at $1,056 found 6 days ago
Southwest Airlines
Wed, Apr 8 - Wed, Apr 15
STL
St. Louis
CNX
Chiang Mai
$1,058 Roundtrip, found 19 hours ago
$1,058
Roundtrip
found 19 hours ago
Select Southwest Airlines flight, departing Wed, Apr 8 from St. Louis to Chiang Mai, returning Wed, Apr 15, priced at $1,058 found 19 hours ago
Alaska Airlines
Tue, Feb 10 - Mon, Feb 23
STL
St. Louis
CNX
Chiang Mai
$1,071 Roundtrip, found 2 days ago
$1,071
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Tue, Feb 10 from St. Louis to Chiang Mai, returning Mon, Feb 23, priced at $1,071 found 2 days ago
Korean Air
Fri, Jan 23 - Mon, Feb 9
STL
St. Louis
CNX
Chiang Mai
$1,107 Roundtrip, found 5 hours ago
$1,107
Roundtrip
found 5 hours ago
Select Korean Air flight, departing Fri, Jan 23 from St. Louis to Chiang Mai, returning Mon, Feb 9, priced at $1,107 found 5 hours ago

Alternative airports near Chiang Mai

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

Select flight to Chiang Mai Intl. CNX. Cheapest and Closest option available. Average driving time to city center is 10 minutes. Flights from $1,289
CNX
Chiang Mai Intl.
CheapestClosest
Average driving time to city center10 min
Flights from $1,289

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX) cost?
Secure a cheap one-way flight from $557 or cheap return flight from $978 from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX) 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 Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX)?
The cheapest month to fly from STL to CNX is January, when there's less demand. Off-peak season is typically when you'll find lower airfares between these airports.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX)?
Expedia's filter tool lets you easily compare airlines, flight times and baggage options all in one place. Tailor the search to your trip, then sort by "Price (lowest to highest)" to find the carrier with the cheapest STL to CNX flight.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX)?
Nonstop flights from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX) 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 travel dates and pick either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STL to CNX?
Typically you'll have the most choice when it comes to flights on a Friday. Tuesdays are often the quietest.* But this can change depending on the season, airline 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 Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX)?
To reach Chiang Mai Intl. Airport (CNX) on schedule, opt for a flight that leaves Lambert-St. Louis Intl. Airport (STL) before 3 PM. The likelihood 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.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX) last-minute?
Booking your flight from STL to CNX right before your getaway is usually more expensive. But if you're flexible with your departure times and dates, you could bag a cheap last-minute fare.
Is it cheaper to book a STL to CNX flight and hotel package?
You'll typically save money by booking a STL to CNX flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it's easy to manage everything in one convenient place. After selecting your ideal accommodations and flights, you can add extras such as tours, activities and car rentals.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Chiang Mai Intl. Airport (CNX)?
If you reserved your STL to CNX flight within the last 24 hours, you may be able to cancel or modify it without fees. Depending on the airline and the fare type you purchased, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Chiang Mai Intl.
Airlines serving
Delta, Korean Air
Roundtrip price
$978
Distance
8416 mi

Book with confidence

St. Louis to Chiang Mai Flights

The cheapest times to fly from St. Louis to Chiang Mai

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 St. Louis to Chiang Mai are during the month of January. You can find some of the cheapest flights from St. Louis to Chiang Mai with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Chiang Mai

Sunday is one of the best days to book for cheap flights from St. Louis to Chiang Mai: 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 St. Louis to Chiang Mai

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 St. Louis to Chiang Mai in 2025. You can also book with separate airlines for your outbound and return journeys, from $557 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 St. Louis to Chiang Mai 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 St. Louis to Chiang Mai 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.

 

St. Louis to Chiang Mai Flights

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*Available to One Key members.