Cheap flights from Denver to Northwest Washington

View AU$121 flight on Mon, 25 Aug. 2025Opens in a new window

Popular airlines from Denver to Northwest Washington

  • Jetstar

    Jetstar

  • Qantas Airways

    Qantas Airways

  • Virgin Australia

    Virgin Australia

  • Scoot

    Scoot

  • American Airlines

    American Airlines

  • Emirates

    Emirates

  • United

    United

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Cheap Flights from Denver (DEN) to Northwest Washington (SEA)

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Mon, 8 Sep. - Wed, 24 Sep.
DEN
Denver
SEA
Seattle
AU$243 Return, found 3 days ago
AU$243
Return
found 3 days ago
Select Alaska Airlines flight, departing Mon, 8 Sep. from Denver to Seattle, returning Wed, 24 Sep., priced at AU$243 found 3 days ago
Delta
Mon, 8 Sep. - Wed, 24 Sep.
DEN
Denver
SEA
Seattle
AU$244 Return, found 3 days ago
AU$244
Return
found 3 days ago
Select Delta flight, departing Mon, 8 Sep. from Denver to Seattle, returning Wed, 24 Sep., priced at AU$244 found 3 days ago
Alaska Airlines
Sat, 16 Aug. - Fri, 22 Aug.
DEN
Denver
SEA
Seattle
AU$253 Return, found 6 days ago
AU$253
Return
found 6 days ago
Select Alaska Airlines flight, departing Sat, 16 Aug. from Denver to Seattle, returning Fri, 22 Aug., priced at AU$253 found 6 days ago
Delta
Sat, 16 Aug. - Fri, 22 Aug.
DEN
Denver
SEA
Seattle
AU$254 Return, found 6 days ago
AU$254
Return
found 6 days ago
Select Delta flight, departing Sat, 16 Aug. from Denver to Seattle, returning Fri, 22 Aug., priced at AU$254 found 6 days ago
Alaska Airlines
Sat, 16 Aug. - Fri, 22 Aug.
DEN
Denver
SEA
Seattle
AU$254 Return, found 6 days ago
AU$254
Return
found 6 days ago
Select Alaska Airlines flight, departing Sat, 16 Aug. from Denver to Seattle, returning Fri, 22 Aug., priced at AU$254 found 6 days ago
United
Fri, 22 Aug. - Tue, 26 Aug.
DEN
Denver
SEA
Seattle
AU$318 Return, found 3 days ago
AU$318
Return
found 3 days ago
Select United flight, departing Fri, 22 Aug. from Denver to Seattle, returning Tue, 26 Aug., priced at AU$318 found 3 days ago

Find the cheapest month to fly from Denver (DEN) to Bellingham (BLI)

May is typically the cheapest month to fly

From AU$350 - AU$764 per traveller.

Graph displaying average flight prices per month

*Available to Expedia members.