Cheap flights from Seattle to Great Diamond Island

View AU$241 flight on Mon, 29 Sep. 2025Opens in a new window

Popular airlines from Seattle to Great Diamond Island

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Cheap Flights from Seattle (SEA) to Great Diamond Island (PWM)

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.

American Airlines
Mon, 29 Sep. - Mon, 20 Oct.
SEA
Seattle
PWM
Portland
AU$499 Return, found 2 days ago
AU$499
Return
found 2 days ago
Select American Airlines flight, departing Mon, 29 Sep. from Seattle to Portland, returning Mon, 20 Oct., priced at AU$499 found 2 days ago
American Airlines
Mon, 29 Sep. - Mon, 20 Oct.
SEA
Seattle
PWM
Portland
AU$549 Return, found 2 days ago
AU$549
Return
found 2 days ago
Select American Airlines flight, departing Mon, 29 Sep. from Seattle to Portland, returning Mon, 20 Oct., priced at AU$549 found 2 days ago
American Airlines
Mon, 29 Sep. - Mon, 20 Oct.
SEA
Seattle
PWM
Portland
AU$557 Return, found 2 days ago
AU$557
Return
found 2 days ago
Select American Airlines flight, departing Mon, 29 Sep. from Seattle to Portland, returning Mon, 20 Oct., priced at AU$557 found 2 days ago
Delta
Mon, 29 Sep. - Mon, 20 Oct.
SEA
Seattle
PWM
Portland
AU$645 Return, found 2 days ago
AU$645
Return
found 2 days ago
Select Delta flight, departing Mon, 29 Sep. from Seattle to Portland, returning Mon, 20 Oct., priced at AU$645 found 2 days ago
United
Mon, 29 Sep. - Mon, 20 Oct.
SEA
Seattle
PWM
Portland
AU$721 Return, found 2 days ago
AU$721
Return
found 2 days ago
Select United flight, departing Mon, 29 Sep. from Seattle to Portland, returning Mon, 20 Oct., priced at AU$721 found 2 days ago
Alaska Airlines
Mon, 29 Sep. - Mon, 20 Oct.
SEA
Seattle
PWM
Portland
AU$894 Return, found 2 days ago
AU$894
Return
found 2 days ago
Select Alaska Airlines flight, departing Mon, 29 Sep. from Seattle to Portland, returning Mon, 20 Oct., priced at AU$894 found 2 days ago

Find the cheapest month to fly from Seattle (SEA) to Portland (PWM)

September is typically the cheapest month to fly

From AU$348 - AU$729 per traveller.

Graph displaying average flight prices per month

*Available to Expedia members.