SEA

£366 Find Cheap Flights from Belfast to Seattle

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 to Seattle departing on 15/7. 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
£634
Multiple Airlines
Wed 20/5Tue 2/6
BFS - SEA • 3 stops
Cheapest one-way flight
£366
Multiple Airlines
Wed 15/7
BFS - SEA • 3 stops
Top airlines
Cheapest • from £693 (return)
Best reviews • 7.1 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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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
Booking Insights
Flight Deals

Cheap Flights from Belfast to Seattle

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Belfast 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 to Seattle

Wed, 20 May - Tue, 2 Jun
Multiple Airlines Logo
06:15 - 09:40
BFS
-
SEA
35h 25m
3 stops
Multiple Airlines Logo
15:40 - 23:20
SEA
-
BFS
23h 40m
3 stops
£634Multiple Airlines
Tue, 1 Sep - Tue, 22 Sep
British Airways Logo
06:30 - 11:35
BHD
-
SEA
13h 05m
1 stop
British Airways Logo
20:20 - 17:35
SEA
-
BHD
13h 15m
1 stop
£693British Airways
Wed, 20 May - Tue, 2 Jun
Multiple Airlines Logo
06:15 - 09:40
BFS
-
SEA
35h 25m
3 stops
Multiple Airlines Logo
15:40 - 21:20
SEA
-
BFS
21h 40m
2 stops
£708Multiple Airlines
Tue, 1 Sep - Tue, 22 Sep
British Airways Logo
09:40 - 20:02
BHD
-
SEA
18h 22m
2 stops
British Airways Logo
20:20 - 17:35
SEA
-
BHD
13h 15m
1 stop
£722British Airways
Sat, 6 Jun - Sat, 13 Jun
Multiple Airlines Logo
06:20 - 16:00
BFS
-
SEA
17h 40m
2 stops
Multiple Airlines Logo
18:15 - 22:40
SEA
-
BFS
20h 25m
2 stops
£751Multiple Airlines
Wed, 20 May - Tue, 2 Jun
British Airways Logo
06:30 - 11:35
BHD
-
SEA
13h 05m
1 stop
British Airways Logo
13:30 - 10:45
SEA
-
BHD
13h 15m
1 stop
£769British Airways
Wed, 20 May - Tue, 2 Jun
Multiple Airlines Logo
07:00 - 09:40
BHD
-
SEA
34h 40m
3 stops
Multiple Airlines Logo
05:45 - 17:50
SEA
-
BHD
28h 05m
3 stops
£776Multiple Airlines
Wed, 20 May - Tue, 2 Jun
British Airways Logo
11:35 - 22:38
BHD
-
SEA
19h 03m
2 stops
British Airways Logo
20:20 - 18:55
SEA
-
BHD
14h 35m
1 stop
£776British Airways
Thu, 21 May - Tue, 2 Jun
American Airlines Logo
06:30 - 11:35
BHD
-
SEA
13h 05m
1 stop
American Airlines Logo
20:20 - 18:55
SEA
-
BHD
14h 35m
1 stop
£790American Airlines
Thu, 21 May - Thu, 4 Jun
American Airlines Logo
12:45 - 11:35
BHD
-
SEA
30h 50m
1 stop
American Airlines Logo
06:00 - 15:30
SEA
-
BHD
25h 30m
2 stops
£793American Airlines
Booking Insights

KAYAK’s insights & trends for Belfast to Seattle flights

Get data-powered insights and trends into flights from Belfast to Seattle to help you find the cheapest flights, the best time to fly and much more.

Which airlines provide the cheapest flights from Belfast to Seattle?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest return tickets from Belfast to Seattle were found on British Airways (£693) and American Airlines (£790).

Good to know - Cheap tickets from Belfast to Seattle

Cheapest flight£366
Flight from Belfast Intl Airport to Seattle

When to book flights from Belfast to Seattle

Are your dates flexible? Find out the best times to travel from Belfast 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 flights from Belfast to Seattle

  • What is the cheapest flight from Belfast to Seattle?

    In the last 3 days, the lowest price for a flight from Belfast to Seattle was £366 for a one-way ticket and £634 for a return.

  • Which airports will I be using when flying from Belfast to Seattle?

    There are 2 airports in Belfast (Belfast Intl and Belfast City.) and only 1 airport in Seattle (Seattle/Tacoma Intl). The cheapest flights are generally found on the Belfast City Airport to Seattle/Tacoma Intl flight route.

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

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

  • Which airline alliances offer flights from Belfast to Seattle?

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

  • How does KAYAK find such low prices on flights from Belfast 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 to Seattle.

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

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

  • What is the Hacker Fare option on flights from Belfast 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 with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Belfast 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 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 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 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 11659 reviews
7.2Comfort
6.4Food
7.5Boarding
7.9Crew
6.9Entertainment
Airline reviews

On time departure and early arrival. Flight attendant very nice.

10.0 ExcellentKathryn, Apr 2026
LAX - OMA
Read more American Airlines reviews

On time departure and early arrival. Flight attendant very nice.

As we approached Denver, we encountered quite a bit of turbulence. I know this can sometimes be the case as I frequently fly this route but not on American. My gripe: Usually a pilot or co-pilot alerts passengers to the possibility of turbulance ahead of time. This did not occur nor did he communiucate during what was a pretty rough ride.

The staff was nice. I appreciated that I was able to take an earlier flight, even though it was last minute. The boarding process felt rather chaotic.

Overall a good experience, however Wifi was not working on the flight.

Airlines should be prohibited from using the seats they get away with.

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.

Older airplane with worn out seats. No entertainment system at all. Connecting to Wi-Fi was problematic and hit and miss.

An delay of almost 3 hours while passengers were already in the plane kept us very uncomfortable. The food was also very limited. A bad experience overall.

I understand that there is a catering issue - water should be the minimum stock. During the flight, not once that the attendants came through with water. The conversations in the kitchen were very loud and they were swearing. I do not expect any white glove service, at the minimum, we should be cordial. It was almost an inconveniece that we were on the flight. And it made us feel if you even dare question us, we'll make you deplane.

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

Information on your arrival and departure airports