฿4,145 Cheap Flights from Boston (BOS) to Seattle (SEA)

View ฿4,145 flight on Wed, 27 May 2026Opens in a new window

Popular airlines from Logan International Airport (BOS) to Seattle-Tacoma International Airport (SEA)

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Cheap Flights from Boston (BOS) to Seattle (SEA)

Prices were available within the past 7 days and start at ฿4,145 for one-way flights and ฿9,580 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, 19 May - Tue, 26 May
BOS
Boston
SEA
Seattle
฿9,580 Return, found 3 days ago
฿9,580
Return
found 3 days ago
Select Delta flight, departing Tue, 19 May from Boston to Seattle, returning Tue, 26 May, priced at ฿9,580 found 3 days ago
Delta
Tue, 19 May - Tue, 26 May
BOS
Boston
SEA
Seattle
฿11,190 Return, found 3 days ago
฿11,190
Return
found 3 days ago
Select Delta flight, departing Tue, 19 May from Boston to Seattle, returning Tue, 26 May, priced at ฿11,190 found 3 days ago
Delta
Wed, 20 May - Wed, 27 May
BOS
Boston
SEA
Seattle
฿11,195 Return, found 2 days ago
฿11,195
Return
found 2 days ago
Select Delta flight, departing Wed, 20 May from Boston to Seattle, returning Wed, 27 May, priced at ฿11,195 found 2 days ago
Delta
Tue, 19 May - Tue, 26 May
BOS
Boston
SEA
Seattle
฿11,355 Return, found 3 days ago
฿11,355
Return
found 3 days ago
Select Delta flight, departing Tue, 19 May from Boston to Seattle, returning Tue, 26 May, priced at ฿11,355 found 3 days ago
Delta
Tue, 19 May - Tue, 26 May
BOS
Boston
SEA
Seattle
฿11,510 Return, found 3 days ago
฿11,510
Return
found 3 days ago
Select Delta flight, departing Tue, 19 May from Boston to Seattle, returning Tue, 26 May, priced at ฿11,510 found 3 days ago
Delta
Wed, 20 May - Wed, 27 May
BOS
Boston
SEA
Seattle
฿11,515 Return, found 2 days ago
฿11,515
Return
found 2 days ago
Select Delta flight, departing Wed, 20 May from Boston to Seattle, returning Wed, 27 May, priced at ฿11,515 found 2 days ago
Delta
Tue, 19 May - Tue, 26 May
BOS
Boston
SEA
Seattle
฿11,675 Return, found 3 days ago
฿11,675
Return
found 3 days ago
Select Delta flight, departing Tue, 19 May from Boston to Seattle, returning Tue, 26 May, priced at ฿11,675 found 3 days ago
Delta
Sat, 21 Nov - Tue, 1 Dec
BOS
Boston
SEA
Seattle
฿12,160 Return, found 3 days ago
฿12,160
Return
found 3 days ago
Select Delta flight, departing Sat, 21 Nov from Boston to Seattle, returning Tue, 1 Dec, priced at ฿12,160 found 3 days ago
American Airlines
Tue, 30 Jun - Wed, 8 Jul
BOS
Boston
SEA
Seattle
฿13,930 Return, found 3 days ago
฿13,930
Return
found 3 days ago
Select American Airlines flight, departing Tue, 30 Jun from Boston to Seattle, returning Wed, 8 Jul, priced at ฿13,930 found 3 days ago
United
Thu, 7 May - Thu, 14 May
BOS
Boston
SEA
Seattle
฿19,555 Return, found 1 day ago
฿19,555
Return
found 1 day ago
Select United flight, departing Thu, 7 May from Boston to Seattle, returning Thu, 14 May, priced at ฿19,555 found 1 day ago

Find the cheapest month to fly from Boston (BOS) to Seattle (SEA)

April is typically the cheapest month to fly

From ฿6,460 - ฿16,195 per traveller.

Frequently asked questions

How much is a flight from Logan Intl. Airport to SEA?
If you're planning on travelling between Logan Intl. Airport (BOS) and Sea-Tac Airport, round-trip journeys start from ฿9,580. This price is based on fares available within the last 7 days on Expedia for flights departing within the next year, so don't delay. Book today and save yourself money and time. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from BOS to SEA?
The majority of flights can be cancelled online, but whether you are charged a fee differs between airlines. If you do have to cancel your trip, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Logan Intl. Airport to SEA that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for Logan Intl. Airport (BOS) to Seattle - Tacoma Intl. Airport (SEA) flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Logan Intl. Airport to Sea-Tac Airport?
With around 4,000 kilometres separating Boston and SeaTac, your flight will be a long one. Pack wisely to make your time on board more comfortable. Things like a sleep mask and some noise-cancelling headphones can make all the difference.
Which airlines fly direct from BOS to Seattle - Tacoma Intl. Airport (SEA)?
With 117 flights every month operating from Logan Intl. Airport to Sea-Tac Airport, Alaska Airlines (AS) is a popular choice. Love some more options? Check out the airfares with Delta Air Lines (DL). This carrier offers 78 flights a month between these airports.
Are Logan Intl. Airport to Sea-Tac Airport flight tickets cheaper when they're purchased at the last minute?
Late planners can sometimes pick up a bargain, with some super cheap fares from Logan Intl. Airport to Sea-Tac Airport arising a few weeks prior to the departure date. If you'd rather book ahead of time, Expedia compares and updates all the best flight deals continuously — as early as a year in advance in some cases. It does depend on the carrier though, as not all airlines advertise prices that far in advance.

Travel information

Origin airport
Logan Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
American Airlines, Delta, United
Return price
฿9,580
Distance
3980 km
Average flight time
4 hours 35 mins
*Available to Expedia members.