BFS - SEA

£404 Find Cheap Flights from Belfast Intl Airport to Seattle – Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Belfast Intl to Seattle departing on 25/10. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Belfast to Seattle, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Belfast to Seattle, as well as popular online travel agencies
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Everything you should know

Cheapest return fare
£751
Multiple Airlines
Wed 15/7Tue 21/7
BFS - SEA • 3 stops
Cheapest one-way flight
£404
Multiple Airlines
Sun 25/10
BFS - SEA • 2 stops
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KAYAK searches hundreds of sites at once to find you the best travel deals.
We hope you love your trip to Seattle!
Flight Deals
Useful Info
Flight Deals

Cheap Flights from Belfast Intl to Seattle (BFS-SEA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Belfast Intl to Seattle that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from Belfast Intl to Seattle

Wed, 15 Jul - Tue, 21 Jul
Multiple Airlines Logo
22:45 - 10:07
BFS
-
SEA
43h 22m
3 stops
Multiple Airlines Logo
15:40 - 19:50
SEA
-
BFS
20h 10m
3 stops
£751Multiple Airlines
Wed, 15 Jul - Tue, 21 Jul
Multiple Airlines Logo
22:45 - 10:07
BFS
-
SEA
43h 22m
3 stops
Multiple Airlines Logo
15:40 - 22:15
SEA
-
BFS
22h 35m
2 stops
£812Multiple Airlines
Wed, 15 Jul - Tue, 21 Jul
Multiple Airlines Logo
06:10 - 20:40
BFS
-
SEA
22h 30m
2 stops
Multiple Airlines Logo
15:40 - 22:50
SEA
-
BFS
23h 10m
2 stops
£813Multiple Airlines
Fri, 10 Jul - Thu, 16 Jul
Multiple Airlines Logo
07:05 - 17:55
BFS
-
SEA
18h 50m
2 stops
Multiple Airlines Logo
15:40 - 19:30
SEA
-
BFS
19h 50m
3 stops
£1,005Multiple Airlines
Fri, 10 Jul - Thu, 16 Jul
Multiple Airlines Logo
07:05 - 20:40
BFS
-
SEA
21h 35m
2 stops
Multiple Airlines Logo
19:00 - 21:45
SEA
-
BFS
18h 45m
2 stops
£1,011Multiple Airlines
Useful Info

Good to know - Cheap tickets from Belfast Intl Airport to Seattle

Cheapest flight£404
Flight from Belfast Intl Airport to Seattle

When to book flights from Belfast Intl to Seattle

Are your dates flexible? Find out the best times to travel from Belfast Intl to Seattle based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated return price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or returns with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking Belfast Intl Airport to Seattle flights

  • What is the cheapest flight from Belfast Intl Airport to Seattle?

    In the last 3 days, the lowest price for a flight from Belfast Intl Airport to Seattle was £404 for a one-way ticket and £751 for a return.

  • Which aircraft models fly most regularly from Belfast Intl Airport to Seattle?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Belfast Intl Airport to Seattle?

    oneworld is the only airline alliance operating flights between Belfast Intl Airport and Seattle.

  • How does KAYAK find such low prices on flights from Belfast Intl Airport to Seattle?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Belfast Intl Airport to Seattle.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Belfast Intl Airport to Seattle?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Belfast Intl Airport is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Belfast Intl Airport to Seattle?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to Seattle with an airline and back to Belfast Intl Airport with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Belfast Intl Airport to Seattle?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Belfast Intl Airport up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Belfast Intl to Seattle

 
See real verified KAYAK customer reviews for airlines flying from Belfast to Seattle. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Belfast Intl to Seattle? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.1
American AirlinesOverall score based on 11670 reviews
7.5Boarding
7.2Comfort
6.8Entertainment
7.9Crew
6.4Food
Airline reviews

Crew was nice, aircraft dated, entertainment same. Internet is expensive and terribly slow. Food pretty bad

6.0 GoodSebastian, Jun 2026
LHR - CLT
Read more American Airlines reviews

Crew was nice, aircraft dated, entertainment same. Internet is expensive and terribly slow. Food pretty bad

Horrible experience. Food was ridiculous, insufficient, and not appetizing at all. They served sugary granola bar for breakfast. Furthermore, my bags were delayed and delivered damaged and American made it impossible to file for damages. Furthermore, the flights were delayed causing unnecessary stress given the connecting flights. It was awful experience, would never want to fly American.

My table was broken so it made it difficult to eat the food during the service. I was also informed that my luggage did not make it with me to Phoenix. I live two hours away so this makes it even more stressful to try and arrange a time for pick up

Very hard to beat a British Airways international flight…the crews are always so amazing! One flight attendant that really stood out was Emma…she was very personable and accommodating with any request we had!!

The passport line was so long that many of us were concerned about missing our flight and some did. It would've helped if a AA representative had gone to the passport check-in sooner to advise that boarding was closing and those flying that were stuck back in the line, needed to come forward with apologies to others. An AA representative did do that but only after boarding had already closed. (They delayed take-off so that more who were running with carry-ons could get to the gate - especially stressful for older people!) Then to be crammed into a seat with barely enough leg room for a thin woman, 5'7", like me, much less for a taller, bigger person was not comfortable, especially if the person in front decided to lean back. Crew was fine, food and entertainment also.

The seat when "flat" was not flat and pad was too thin to cover it.

Awful customer service, horrible experience. We travel a lot domestic & international- worst flights to/from ever. Brief bkgd as Inhate to relive this experience: booked and chose 2 seats 4 months prior in Premium Economy - last row end seats close to bathroom, no one behind us, plenty of legroom;, underwear storage — flown this was on other airlines, love it. We receive notice 4 days before scheduled overseas flight - plane has changed, new seats assigned. Seats are split into single seats, opposites of the plane, FRONT Row so no reachable storage. Called BOTH British Air & America. American “switched planes and the seats you want are taken;” British Air “Yes, we’ll be glad to accommodate you (type type type). Just ask at the Gate and someone will give you new boarding passes with seats together in middle, OK?” — OK. —At Gate the attendant looks us up saying “No, it is an overbooked flight and yours are the only seats available.” But but but wait, “We were TOLD our seats had been switched and seated together?” Gate attendant “Well they were wrong and don’t change your seats. Your original seats are where you’ll sit.”. Right. No help WHATSOEVER. We sit opposite on way there, wife VERY disgruntled, a Tol 5 worst ways to start a 3-week bus tour of UK. We promise to NEVER FLY AMERICAN OR BROTISH AIR EVER, and we have 3 more extensive trips planned..

They lost my bag. ... And I asked them 3 times to 3 different people if my checked bag will maKe it all the way - they all confirmed and at the end it was left at the connection... Bravo

Plane was super cold. No entertainment unless you were with mileage program Getting off the plane was super slow

British Airways is an excellent airline. Comfort, food and airline personnel.

Everything you need to know for your flight from Belfast Intl to Seattle

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