Cheap flights from Seattle to Koh Samui Islands from CA $642

View CA $642 flight on Tue, Nov. 4, 2025Opens in a new window

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Cheap flights from Seattle (SEA) to Koh Samui Islands (USM)

Prices were available within the past 7 days and start at CA $642 for one-way flights and CA $1,028 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Singapore Airlines
Tue, Nov. 4 - Mon, Nov. 10
SEA
Seattle
USM
Koh Samui
CA $1,028 Roundtrip, found 6 hours ago
CA $1,028
Roundtrip
found 6 hours ago
Select Singapore Airlines flight, departing Tue, Nov. 4 from Seattle to Koh Samui, returning Mon, Nov. 10, priced at CA $1,028 found 6 hours ago
Singapore Airlines
Tue, Nov. 4 - Mon, Nov. 10
SEA
Seattle
USM
Koh Samui
CA $1,081 Roundtrip, found 6 hours ago
CA $1,081
Roundtrip
found 6 hours ago
Select Singapore Airlines flight, departing Tue, Nov. 4 from Seattle to Koh Samui, returning Mon, Nov. 10, priced at CA $1,081 found 6 hours ago
EVA Airways
Tue, Nov. 4 - Mon, Nov. 10
SEA
Seattle
USM
Koh Samui
CA $1,449 Roundtrip, found 6 hours ago
CA $1,449
Roundtrip
found 6 hours ago
Select EVA Airways flight, departing Tue, Nov. 4 from Seattle to Koh Samui, returning Mon, Nov. 10, priced at CA $1,449 found 6 hours ago
STARLUX Airlines
Thu, Sep. 4 - Mon, Sep. 15
SEA
Seattle
USM
Koh Samui
CA $1,485 Roundtrip, found 4 days ago
CA $1,485
Roundtrip
found 4 days ago
Select STARLUX Airlines flight, departing Thu, Sep. 4 from Seattle to Koh Samui, returning Mon, Sep. 15, priced at CA $1,485 found 4 days ago
China Airlines
Sun, Sep. 28 - Wed, Oct. 8
SEA
Seattle
USM
Koh Samui
CA $1,700 Roundtrip, found 16 hours ago
CA $1,700
Roundtrip
found 16 hours ago
Select China Airlines flight, departing Sun, Sep. 28 from Seattle to Koh Samui, returning Wed, Oct. 8, priced at CA $1,700 found 16 hours ago
Qatar Airways
Sun, Sep. 28 - Wed, Oct. 8
SEA
Seattle
USM
Koh Samui
CA $1,892 Roundtrip, found 16 hours ago
CA $1,892
Roundtrip
found 16 hours ago
Select Qatar Airways flight, departing Sun, Sep. 28 from Seattle to Koh Samui, returning Wed, Oct. 8, priced at CA $1,892 found 16 hours ago
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