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Siem Reap

$3,206+ Cheap flights from St. Louis (STL) to Siem Reap

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/29. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SAI
mar. 17 — mar. 241
mar. 3/17
mar. 3/24
1 adult, Economy
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Cheap flight deals from St. Louis to Siem Reap

Cheapest flights from St. Louis to Siem Reap
Explore the most affordable flight options available from St. Louis to Siem Reap. Find the lowest fares from popular airlines and budget airlines, with prices last updated on febrero 15, 2026.

This Flightnetwork deal was found by Cheapflights users on 2/11. 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 Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 3/2910:33 am
STL
-
SAI
3 stops34h 27m
Multiple Airlines
dom. 4/54:00 pm
SAI
-
STL
3 stops35h 24m
Multiple Airlines
Deal found 2/11$3,206

Find flight deals from St. Louis to Siem Reap

Keep the following information in mind while searching for St. Louis to Siem Reap flight deals. Data was last updated febrero 15, 2026.

Most accurate provider

Expedia
1 star

Most trusted provider

Expedia
3 stars

Round-trip from

$3,206
(Flightnetwork)
Provider with most accurate pricing for Lambert-St Louis-Siem Reap–Angkor Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Siem Reap–Angkor Intl flights.
Search Deals
From Lambert-St Louis to Siem Reap
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Siem Reap 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 febrero 15, 2026.
Use the filters below to find and compare flights from St. Louis to Siem Reap that are best for you.

Fly from

St. Louis

Fly to

Siem Reap

Route

Depart

Return

Price

St. LouisSiem Reap

STL - SAI

STLSAI

Lambert-St Louis

dom. 3/29

10:33 am-9:00 am

3 stops34h 27m

Siem Reap–Angkor Intl

dom. 4/5

4:00 pm-3:24 pm

3 stops35h 24m

$3,206

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/11

Best time to book a flight from St. Louis to Siem Reap

Have a flexible travel schedule? Discover the best time to fly to Siem Reap 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.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Siem Reap
No data available for this route at this time. Please check back soon.

Related info for your journey

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

  • What airport do you fly from for flights from St. Louis to Siem Reap?

    Most people fly from Lambert-St Louis (STL) if they book a flight from St. Louis to Siem Reap. Lambert-St Louis is conveniently located just 12.7 mi from St. Louis’s city center.

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

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

  • How can I find direct flights from St. Louis to Siem Reap?

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

  • Can I find deals for business class flights from St. Louis to Siem Reap?

    Yes. Cheapflights offers flight deals from St. Louis to Siem Reap by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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