$168+ Cheap flights from Boston to Seattle (BOS - SEA)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/27. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — SEA
Oct 15 — Oct 221
Round-trip
1 adult, Economy
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Find cheap flights from Boston to Seattle with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Boston Logan Intl to Seattle/Tacoma Intl are usually found in March or January, booked 85 days in advance, depart on a Wednesday or Tuesday and return on a Wednesday
Cheap flight deals from Boston to Seattle
Cheapest
Best
Last-minute
One-way
Cheapest flights from Boston to SeattleExplore the most affordable flight options available from Boston to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2026.
Explore the most affordable flight options available from Boston to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2026.
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/62:50 pm -
2 stops10h 50m
Mon 10/2612:10 am -
2 stops11h 45m
Deal found 9/14![Southwest logo]()
$319
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:35 am -
2 stops11h 45m
Tue 10/2712:10 am -
1 stop8h 00m
Deal found 9/14![Southwest logo]()
$321
This Cheapflightsfares deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/177:20 pm -
Nonstop6h 22m
Wed 10/2111:55 pm -
Nonstop5h 21m
Deal found 9/9![JetBlue logo]()
$324
This Alaska Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/37:03 am -
1 stop13h 52m
Tue 11/39:20 pm -
Nonstop5h 20m
Deal found 9/11![Alaska Airlines logo]()
$327
This KAYAK deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/217:20 pm -
Nonstop6h 22m
Sat 10/2411:53 pm -
Nonstop5h 21m
Deal found 9/10![JetBlue logo]()
$331
This Expedia deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/297:51 am -
1 stop18h 46m
Fri 10/307:18 am -
Nonstop5h 37m
Deal found 9/11![Alaska Airlines logo]()
$332
This CheapOair deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:20 pm -
Nonstop6h 22m
Tue 10/1311:55 pm -
Nonstop5h 21m
Deal found 9/14![JetBlue logo]()
$333
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:50 pm -
1 stop10h 50m
Mon 10/1912:10 am -
1 stop9h 20m
Deal found 9/14![Southwest logo]()
$335
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/292:35 pm -
2 stops13h 05m
Thu 11/511:10 am -
2 stops9h 45m
Deal found 9/14![Southwest logo]()
$336
This lol.travel deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:20 pm -
Nonstop6h 22m
Sat 10/1711:55 pm -
Nonstop5h 21m
Deal found 9/14![JetBlue logo]()
$339
Best flights from Boston to SeattleDiscover carefully curated flight deals from Boston to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
Discover carefully curated flight deals from Boston to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:50 pm -
1 stop10h 50m
Mon 10/1912:10 am -
2 stops11h 45m
Deal found 9/14![Southwest logo]()
$341
This JetBlue deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/197:20 pm -
Nonstop6h 22m
Sat 10/2410:15 pm -
1 stop9h 26m
Deal found 9/11![JetBlue logo]()
$420
This United Airlines deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/610:36 am -
1 stop8h 15m
Sun 10/117:00 am -
1 stop7h 52m
Deal found 9/12![United Airlines logo]()
$420
This Alaska Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/37:08 am -
Nonstop6h 22m
Sun 12/611:10 pm -
1 stop13h 17m
Deal found 9/10![Alaska Airlines logo]()
$437
This Delta deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/1010:40 am -
Nonstop6h 30m
Mon 12/1410:52 pm -
Nonstop5h 28m
Deal found 9/13![Delta logo]()
$447
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/241:55 pm -
2 stops10h 50m
Tue 10/279:00 am -
2 stops9h 30m
Deal found 9/10![Southwest logo]()
$364
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/205:15 am -
2 stops12h 05m
Sat 10/249:10 am -
2 stops10h 00m
Deal found 9/10![Southwest logo]()
$364
This Alaska Airlines deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/245:42 pm -
1 stop7h 57m
Tue 10/64:54 pm -
1 stop9h 27m
Deal found 9/13![Alaska Airlines logo]()
$455
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/135:15 am -
2 stops12h 05m
Mon 10/1912:10 am -
2 stops11h 45m
Deal found 9/14![Southwest logo]()
$386
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/162:35 pm -
2 stops13h 25m
Sat 10/1712:10 am -
1 stop8h 00m
Deal found 9/14![Southwest logo]()
$432
This Southwest deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:50 pm -
1 stop10h 50m
Mon 11/212:15 am -
2 stops12h 35m
Deal found 9/12![Southwest logo]()
$442
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/110:10 am -
2 stops15h 20m
Mon 10/512:10 am -
2 stops11h 45m
Deal found 9/14![Southwest logo]()
$466
Last-minute flights from Boston to SeattleDiscover last-minute flight deals from Boston to Seattle. Data last updated September 15, 2026 and is based on user searches.
Discover last-minute flight deals from Boston to Seattle. Data last updated September 15, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/62:50 pm -
2 stops10h 50m
Mon 10/2612:10 am -
2 stops11h 45m
Deal found 9/14![Southwest logo]()
$319
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:35 am -
2 stops11h 45m
Tue 10/2712:10 am -
1 stop8h 00m
Deal found 9/14![Southwest logo]()
$321
This CheapOair deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:20 pm -
Nonstop6h 22m
Tue 10/1311:55 pm -
Nonstop5h 21m
Deal found 9/14![JetBlue logo]()
$333
This lol.travel deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:20 pm -
Nonstop6h 22m
Sat 10/1711:55 pm -
Nonstop5h 21m
Deal found 9/14![JetBlue logo]()
$339
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:50 pm -
1 stop10h 50m
Mon 10/1912:10 am -
1 stop9h 20m
Deal found 9/14![Southwest logo]()
$335
This Cheapflightsfares deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/177:20 pm -
Nonstop6h 22m
Wed 10/2111:55 pm -
Nonstop5h 21m
Deal found 9/9![JetBlue logo]()
$324
This KAYAK deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/217:20 pm -
Nonstop6h 22m
Sat 10/2411:53 pm -
Nonstop5h 21m
Deal found 9/10![JetBlue logo]()
$331
This Expedia deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/297:51 am -
1 stop18h 46m
Fri 10/307:18 am -
Nonstop5h 37m
Deal found 9/11![Alaska Airlines logo]()
$332
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/292:35 pm -
2 stops13h 05m
Thu 11/511:10 am -
2 stops9h 45m
Deal found 9/14![Southwest logo]()
$336
One-way flights from Boston to SeattleSearch for one-way flight options from Boston to Seattle. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
Search for one-way flight options from Boston to Seattle. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2711:12 am -
2 stops26h 47m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$168
This KAYAK deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/177:20 pm -
Nonstop6h 22m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![JetBlue logo]()
$171
This Kiwi.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1012:15 pm -
2 stops29h 57m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$172
This KAYAK deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:20 pm -
Nonstop6h 22m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![JetBlue logo]()
$173
This Super.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/71:00 pm -
1 stop10h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![JetBlue logo]()
$174
This KAYAK deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/207:20 pm -
Nonstop6h 22m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![JetBlue logo]()
$175
This Kiwi.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2112:57 pm -
2 stops23h 01m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$179
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/134:20 pm -
1 stop11h 25m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Southwest logo]()
$182
Find flight deals from Boston to Seattle
Discover tips and strategies to find the most affordable flight options for your journey from Boston (BOS) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $319 (Southwest) |
One-way from | $168 (Kiwi.com) |
Popular in | December |
Cheapest in | March |
Average price | $409 |
Good round-trip deal | $425 or less |
Good one-way deal | $240 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Boston to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated September 15, 2026.
Use the filters below to find and compare flights from Boston to Seattle that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Wed 11/4
5:55 pm-11:30 pm
1 stop8h 35m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$187
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Sat 10/24
2:15 pm-8:37 pm
1 stop9h 22m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$187
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Sat 10/24
1:25 pm-9:45 pm
2 stops11h 20m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$192
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Tue 11/3
1:20 pm-10:45 pm
2 stops12h 25m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$192
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Wed 10/7
1:00 pm-8:45 pm
1 stop10h 45m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$193
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Thu 11/12
6:30 pm-12:45 am
1 stop9h 15m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$204
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Mon 11/16
7:10 am-12:50 pm
1 stop8h 40m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$204
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Thu 11/5
2:25 pm-12:45 am
2 stops13h 20m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$209
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Mon 11/2
7:55 am-11:20 am
Nonstop6h 25m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$224
Quickest round-trip
BostonSeattle
BOS Boston Logan Intl - SEA Seattle/Tacoma Intl
BOSSEA
Boston Logan Intl
Wed 10/28
9:03 am-12:20 pm
Nonstop6h 17m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-3:00 am
Nonstop0h 00m
$224
Showing 1-10 of 23 resultsSorted by cheapest first
Compare providers for flights from Boston to Seattle
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Boston to Seattle in September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*1 star |
- Most accurate provider: When it comes to deals on Boston-Seattle flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Boston-Seattle flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Boston-Seattle flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Boston-Seattle flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Boston-Seattle flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Boston to Seattle
Have a flexible travel schedule? Discover the best time to fly to Seattle from Boston with our price prediction graph.
BOS-SEA
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Boston to Seattle
Prices
Airlines
Delays
How far ahead should I book a flight from Boston to Seattle?
The price you pay for your flight from Boston to Seattle may vary depending on when you book. For the best chance of a lower fare, look to book 84 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Boston to Seattle?
Currently, March is the cheapest month in which you can book a flight from Boston to Seattle (average of $355). Flying from Boston to Seattle in December is currently the most expensive (average of $524). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from BOS to SEA?
Find hourly flight availability from Boston to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 15, 2026.
When flying from Boston to Seattle, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
How often are flights from Boston to Seattle delayed?
About 17% of weekly flights between Boston and Seattle have experienced delays in the past year, with the average delay time being 161 minutes.
What is the most punctual flight time for Boston to Seattle flights?
Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Wednesday tends to have the lowest number of delays on this route, whereas Thursday has historically faced a higher average of delays compared to other days of the week.
Which airline has the best punctuality record on Boston to Seattle flights?
Over the last year, Delta have had the lowest number of delays on this route, with just 16% of flights being delayed.
The best insider tips for Boston to Seattle flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Boston to Seattle trip
Our travel experts
Reviews of airlines servicing Seattle
Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated September 15, 2026.
Peruse reviews from past customers who have flown with Alaska Airlines,Delta, andUnited Airlines from Boston to Seattle to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Comfort
7.8
Boarding
8.1
Entertainment
7.0
Overall
7.9
Crew
8.5
Food
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Boarding
8.1
Entertainment
7.0
Overall
7.9
Crew
8.5
Food
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Boarding
8.1
Entertainment
7.0
Overall
7.9
Crew
8.5
Food
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Boarding
8.1
Entertainment
7.0
Overall
7.9
Crew
8.5
Food
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Boarding
8.1
Entertainment
7.0
Overall
7.9
Crew
8.5
Food
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Boarding
8.1
Entertainment
7.0
Overall
7.9
Crew
8.5
Food
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Related info for your journey
Find useful and relevant information for your journey from Boston to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsSeaTac
Renton
Tacoma
Lacey
Leavenworth
Olympia
Tukwila
Snoqualmie
Puyallup
Lynnwood
Centralia
Kent
Tumwater
Ellensburg
Issaquah
Marysville
Ocean Shores
Lakewood
Fife
Poulsbo
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Boston and Seattle flights
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Other flights from Boston
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Top 8 airlines flying from Boston to Seattle
Discover the top 8 airlines that operate flights from Boston to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated September 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$98 | Average$278 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$174 | Average$390 | FlexibilityNo cancel fee | On-time83% | |
| Cheapest$190 | Average$435 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$198 | Average$416 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$236 | Average$450 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$254 | Average$429 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$267 | Average$464 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$298 | Average$438 | FlexibilityNo cancel fee | On-time63% |