Cheap Flights from Koh Samui to Siem Reap

View €220 flight on Thu, 15 Jan 2026Opens in a new window

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Cheap flights from Koh Samui to Siem Reap (USM-SAI)

Prices were available within the past 7 days and start at €220 for one-way flights and €387 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Thai Airways International
Sun, 18 Jan - Wed, 21 Jan
USM
Koh Samui
SAI
Siem Reap
€387 Return, found 2 days ago
€387
Return
found 2 days ago
Select Thai Airways International flight, departing Sun, 18 Jan from Koh Samui to Siem Reap, returning Wed, 21 Jan, priced at €387 found 2 days ago
Thai Airways International
Sun, 18 Jan - Wed, 21 Jan
USM
Koh Samui
SAI
Siem Reap
€390 Return, found 2 days ago
€390
Return
found 2 days ago
Select Thai Airways International flight, departing Sun, 18 Jan from Koh Samui to Siem Reap, returning Wed, 21 Jan, priced at €390 found 2 days ago
Thai Airways International
Wed, 14 Jan - Wed, 21 Jan
USM
Koh Samui
SAI
Siem Reap
€394 Return, found 4 days ago
€394
Return
found 4 days ago
Select Thai Airways International flight, departing Wed, 14 Jan from Koh Samui to Siem Reap, returning Wed, 21 Jan, priced at €394 found 4 days ago
Thai Airways International
Sun, 18 Jan - Wed, 21 Jan
USM
Koh Samui
SAI
Siem Reap
€395 Return, found 2 days ago
€395
Return
found 2 days ago
Select Thai Airways International flight, departing Sun, 18 Jan from Koh Samui to Siem Reap, returning Wed, 21 Jan, priced at €395 found 2 days ago
Thai Airways International
Wed, 14 Jan - Wed, 21 Jan
USM
Koh Samui
SAI
Siem Reap
€398 Return, found 4 days ago
€398
Return
found 4 days ago
Select Thai Airways International flight, departing Wed, 14 Jan from Koh Samui to Siem Reap, returning Wed, 21 Jan, priced at €398 found 4 days ago
Bangkok Airways
Tue, 13 Jan - Tue, 20 Jan
USM
Koh Samui
SAI
Siem Reap
€399 Return, found 5 days ago
€399
Return
found 5 days ago
Select Bangkok Airways flight, departing Tue, 13 Jan from Koh Samui to Siem Reap, returning Tue, 20 Jan, priced at €399 found 5 days ago
*Available to Expedia members.