Cheapest return flights from Singapore to Seattle in September from $675

Best time to book flights for Singapore (SIN) to Seattle (SEA) flights at AirHint

AirHint found the following cheapest return flights from Singapore (SIN) to Seattle (SEA) in September 2025 (see full year).

Return flights

18 Sep - 25 Sep Asiana Airlines
09 Sep - 12 Sep STARLUX Airlines
09 Sep - 16 Sep STARLUX Airlines
14 Sep - 25 Sep STARLUX Airlines
05 Sep - 14 Sep STARLUX Airlines
26 Sep - 28 Sep STARLUX Airlines
05 Sep - 13 Sep STARLUX Airlines
18 Sep - 23 Sep United
18 Sep - 30 Sep United
13 Sep - 27 Sep United
18 Sep - 04 Oct Delta

Also check the deals for one-way flights from Singapore to Seattle in September.

Skyscanner

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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