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Chiang Mai

$540+ Cheap flights from St. Louis (STL) to Chiang Mai (CNX)

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 1/26. Fares are subject to change and may not be available on all flights or dates of travel.
STL — CNX
Aug 21 — Aug 281
Thu 8/21
Thu 8/28
1 adult, Economy
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Cheap flight deals from St. Louis to Chiang Mai

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Chiang Mai (CNX). 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 August 16, 2025.

Round-trip from

$1,008
(SmartFares)

One-way from

$540
(Delta)
From Lambert-St Louis to Chiang Mai
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One-way flight from Lambert-St Louis to Chiang Mai
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Find flight deals from St. Louis to Chiang Mai

Cheapest flights from St. Louis to Chiang Mai
Explore the most affordable flight options available from St. Louis to Chiang Mai. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 16, 2025.

This SmartFares deal was found by Cheapflights users on 8/16. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/156:00 amSTL - CNX
2 stops29h 40mMultiple Airlines
Sun 9/2112:45 amCNX - STL
2 stops35h 14mMultiple Airlines
Deal found 8/16$1,008
This SmartFares deal was found by Cheapflights users on 8/14. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/286:00 amSTL - CNX
2 stops29h 40mMultiple Airlines
Sat 10/412:45 amCNX - STL
2 stops35h 18mMultiple Airlines
Deal found 8/14$1,039
This Delta deal was found by Cheapflights users on 8/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/196:00 amSTL - CNX
2 stops27h 55mDelta
Tue 9/2311:15 pmCNX - STL
2 stops34h 45mDelta
Deal found 8/15$1,068
This SmartFares deal was found by Cheapflights users on 8/16. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/303:35 pmSTL - CNX
2 stops30h 50mMultiple Airlines
Tue 10/711:35 amCNX - STL
2 stops48h 28mMultiple Airlines
Deal found 8/16$1,087
This oojo deal was found by Cheapflights users on 8/14. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/286:30 pmSTL - CNX
2 stops27h 50mChina Airlines
Sun 10/511:20 amCNX - STL
2 stops48h 43mChina Airlines
Deal found 8/14$1,149
This oojo deal was found by Cheapflights users on 8/15. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/226:30 pmSTL - CNX
2 stops27h 55mEVA Air
Wed 10/111:35 amCNX - STL
2 stops48h 24mEVA Air
Deal found 8/15$1,152
This Delta deal was found by Cheapflights users on 8/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/227:40 amSTL - CNX
2 stops26h 15mDelta
Wed 10/111:15 pmCNX - STL
2 stops37h 23mDelta
Deal found 8/16$1,168
This Korean Air deal was found by Cheapflights users on 8/13. 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 Korean Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/198:40 amSTL - CNX
2 stops25h 15mKorean Air
Tue 9/2311:15 pmCNX - STL
2 stops35h 54mKorean Air
Deal found 8/13$1,244

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Chiang Mai 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 August 16, 2025.
Use the filters below to find and compare flights from St. Louis to Chiang Mai that are best for you.

Fly from

St. Louis

Fly to

Chiang Mai

Route

Depart

Return

Price

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Mon 9/15

6:00 am-11:40 pm

2 stops29h 40m

Chiang Mai

Sun 9/21

12:45 am-11:59 pm

2 stops35h 14m

$1,008

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Sun 9/28

6:00 am-11:40 pm

2 stops29h 40m

Chiang Mai

Sat 10/4

12:45 am-12:03 am

2 stops35h 18m

$1,039

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Fri 9/19

6:00 am-9:55 pm

2 stops27h 55m

Chiang Mai

Tue 9/23

11:15 pm-10:00 pm

2 stops34h 45m

$1,068

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Tue 9/30

3:35 pm-10:25 am

2 stops30h 50m

Chiang Mai

Tue 10/7

11:35 am-12:03 am

2 stops48h 28m

$1,087

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Sun 9/28

6:30 pm-10:20 am

2 stops27h 50m

Chiang Mai

Sun 10/5

11:20 am-12:03 am

2 stops48h 43m

$1,149

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Mon 9/22

6:30 pm-10:25 am

2 stops27h 55m

Chiang Mai

Wed 10/1

11:35 am-11:59 pm

2 stops48h 24m

$1,152

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Mon 9/22

7:40 am-9:55 pm

2 stops26h 15m

Chiang Mai

Wed 10/1

11:15 pm-12:38 am

2 stops37h 23m

$1,168

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Fri 9/19

8:40 am-9:55 pm

2 stops25h 15m

Chiang Mai

Tue 9/23

11:15 pm-11:09 pm

2 stops35h 54m

$1,244

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Tue 1/27

10:00 am-11:05 pm

2 stops48h 05m

$540

St. LouisChiang Mai

STL - CNX

STLCNX

Lambert-St Louis

Wed 1/28

7:05 pm-11:05 pm

2 stops39h 00m

$540

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/15

Showing 1-10 of 19 results
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Best time to book a flight from St. Louis to Chiang Mai

Have a flexible travel schedule? Discover the best time to fly to Chiang Mai 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.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Chiang Mai. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

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

  • How can I find direct flights from St. Louis to Chiang Mai?

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

  • Can I find deals for business class flights from St. Louis to Chiang Mai?

    Yes. Cheapflights offers flight deals from St. Louis to Chiang Mai 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 Chiang Mai?

    Currently, September is the cheapest month in which you can book a flight from St. Louis to Chiang Mai (average of $1,006). Flying from St. Louis to Chiang Mai in December is currently the most expensive (average of $1,624). 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

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