$140 Cheap United flights Washington (IAD) to Boise (BOI)

View $140 flight on Sat, Aug 16, 2025Opens in a new window

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$140 Cheap United flights Washington (IAD) to Boise (BOI)

Prices were available within the past 7 days and start at $140 for one-way flights and $279 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Wed, Oct 15 - Tue, Oct 21
IAD
Washington
BOI
Boise
$279 Roundtrip, found 2 days ago
$279
Roundtrip
found 2 days ago
Select United flight, departing Wed, Oct 15 from Washington to Boise, returning Tue, Oct 21, priced at $279 found 2 days ago
United
Wed, Oct 15 - Tue, Oct 21
IAD
Washington
BOI
Boise
$297 Roundtrip, found 2 days ago
$297
Roundtrip
found 2 days ago
Select United flight, departing Wed, Oct 15 from Washington to Boise, returning Tue, Oct 21, priced at $297 found 2 days ago
United
Wed, Oct 15 - Tue, Oct 21
IAD
Washington
BOI
Boise
$311 Roundtrip, found 2 days ago
$311
Roundtrip
found 2 days ago
Select United flight, departing Wed, Oct 15 from Washington to Boise, returning Tue, Oct 21, priced at $311 found 2 days ago
United
Sat, Aug 30 - Sun, Aug 31
IAD
Washington
BOI
Boise
$314 Roundtrip, found 2 days ago
$314
Roundtrip
found 2 days ago
Select United flight, departing Sat, Aug 30 from Washington to Boise, returning Sun, Aug 31, priced at $314 found 2 days ago
United
Sun, Sep 7 - Tue, Sep 9
IAD
Washington
BOI
Boise
$316 Roundtrip, found 3 days ago
$316
Roundtrip
found 3 days ago
Select United flight, departing Sun, Sep 7 from Washington to Boise, returning Tue, Sep 9, priced at $316 found 3 days ago
United
Sat, Aug 30 - Sun, Aug 31
IAD
Washington
BOI
Boise
$318 Roundtrip, found 2 days ago
$318
Roundtrip
found 2 days ago
Select United flight, departing Sat, Aug 30 from Washington to Boise, returning Sun, Aug 31, priced at $318 found 2 days ago
Flights from Washington (IAD) to Boise (BOI)
Origin airport
Washington Dulles Intl.
Destination airport
Boise
Airlines serving
Alaska Airlines, American Airlines, Delta, Hawaiian Airlines, Southwest Airlines, United
Popular airline
Alaska Airlines
Distance
2020 mi

Frequently asked questions

How much is a United Airlines flight from Washington Dulles Intl. Airport (IAD) to Boise Airport (BOI)?
You can discover affordable return United Airlines flights from $279 from IAD to BOI by sorting your results from "Price (lowest to highest)" on Expedia. Or search for options from $140 for a one-way trip.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from IAD to BOI with United Airlines?
Search for one-way or round-trip flights to Boise in January or December. You could find cheaper fares with United Airlines during these off-season months.
What is the cheapest time to book flights from Washington Dulles Intl. Airport (IAD) to Boise Airport (BOI) with United Airlines?
To find cheap United Airlines fares from Washington Dulles Intl. Airport (IAD) to Boise Airport (BOI), start searching one to three months before your intended departure. Securing domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also impact the cost. Sunday is generally the cheapest, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your journey on a Sunday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does United Airlines fly nonstop from Washington Dulles Intl. Airport (IAD) to Boise Airport (BOI)?
Fill in your dates, click search and use the "Nonstop" filter on Expedia to browse any direct flights from IAD to BOI with United Airlines or another carrier.
What is the earliest United Airlines flight from IAD to BOI?
To find the earliest departures from IAD to BOI with United Airlines, filter your search by "Morning" and "Early Morning." Booking an early flight generally means you'll experience fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does United Airlines fly into in Boise?
Boise Airport (BOI) is the primary Boise hub for United Airlines flights from Washington Dulles Intl. Airport (IAD).
Why fly with United Airlines from IAD to BOI?
A rewarding loyalty program and the ability to collect points through United Mileage Plus are the start of the reasons to leave from IAD to BOI with United Airlines. Plus, when you sign up to Expedia's free One Key™ program, you can receive OneKeyCash™* on top of any airline loyalty program earnings. It's yours to spend on future bookings.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my United Airlines flight from Washington Dulles Intl. Airport (IAD) to Boise Airport (BOI)?
Depending on the ticket type you purchased, a fee will generally apply if you change or cancel your booking more than 24 hours after it has been confirmed. To find tickets with more flexibility, select our "No cancel fee" or "Changes included" filter while looking for flights. For more information on modifying or canceling your reservation, visit "Trips," select your flight and tick "Manage Booking."

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