Cheap flights from Washington to Southwest Idaho

View AU$262 flight on Thu, 4 Sep. 2025Opens in a new window

Popular airlines from Washington to Southwest Idaho

  • American Airlines

    American Airlines

  • Delta

    Delta

  • United

    United

  • Alaska Airlines

    Alaska Airlines

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Cheap Flights from Washington (WAS) to Southwest Idaho (BOI)

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.

United
Thu, 28 Aug. - Thu, 4 Sep.
IAD
Washington
BOI
Boise
AU$621 Return, found 3 hours ago
AU$621
Return
found 3 hours ago
Select United flight, departing Thu, 28 Aug. from Washington to Boise, returning Thu, 4 Sep., priced at AU$621 found 3 hours ago
United
Thu, 28 Aug. - Thu, 4 Sep.
IAD
Washington
BOI
Boise
AU$622 Return, found 3 hours ago
AU$622
Return
found 3 hours ago
Select United flight, departing Thu, 28 Aug. from Washington to Boise, returning Thu, 4 Sep., priced at AU$622 found 3 hours ago
Alaska Airlines
Thu, 28 Aug. - Thu, 4 Sep.
IAD
Washington
BOI
Boise
AU$665 Return, found 3 hours ago
AU$665
Return
found 3 hours ago
Select Alaska Airlines flight, departing Thu, 28 Aug. from Washington to Boise, returning Thu, 4 Sep., priced at AU$665 found 3 hours ago
Alaska Airlines
Thu, 28 Aug. - Thu, 4 Sep.
IAD
Washington
BOI
Boise
AU$666 Return, found 3 hours ago
AU$666
Return
found 3 hours ago
Select Alaska Airlines flight, departing Thu, 28 Aug. from Washington to Boise, returning Thu, 4 Sep., priced at AU$666 found 3 hours ago
American Airlines
Thu, 28 Aug. - Thu, 4 Sep.
DCA
Washington
BOI
Boise
AU$693 Return, found 3 hours ago
AU$693
Return
found 3 hours ago
Select American Airlines flight, departing Thu, 28 Aug. from Washington to Boise, returning Thu, 4 Sep., priced at AU$693 found 3 hours ago
Delta
Thu, 28 Aug. - Thu, 4 Sep.
DCA
Washington
BOI
Boise
AU$727 Return, found 3 hours ago
AU$727
Return
found 3 hours ago
Select Delta flight, departing Thu, 28 Aug. from Washington to Boise, returning Thu, 4 Sep., priced at AU$727 found 3 hours ago

Find the cheapest month to fly from Washington (WAS) to Boise (BOI)

October is typically the cheapest month to fly

From AU$267 - AU$899 per traveller.

Graph displaying average flight prices per month

*Available to Expedia members.