SEA

£507 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 8/7. 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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41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest return fare
£556
British Airways
Thu 22/10Mon 26/10
BHD - SEA • 1 stop
Cheapest one-way flight
£507
Multiple Airlines
Wed 8/7
BFS - SEA • 3 stops
Top airlines
Cheapest • from £556 (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

Thu, 22 Oct - Mon, 26 Oct
British Airways Logo
06:30 - 11:35
BHD
-
SEA
13h 05m
1 stop
British Airways Logo
19:50 - 18:35
SEA
-
BHD
15h 45m
1 stop
£556British Airways
Thu, 22 Oct - Mon, 26 Oct
British Airways Logo
20:35 - 11:35
BHD
-
SEA
23h 00m
1 stop
British Airways Logo
15:10 - 16:05
SEA
-
BHD
17h 55m
2 stops
£576British Airways
Thu, 22 Oct - Mon, 26 Oct
British Airways Logo
12:45 - 00:14
BHD
-
SEA
19h 29m
2 stops
British Airways Logo
15:10 - 14:15
SEA
-
BHD
16h 05m
2 stops
£581British Airways
Thu, 24 Sep - Sun, 27 Sep
British Airways Logo
14:20 - 11:35
BHD
-
SEA
29h 15m
1 stop
British Airways Logo
20:20 - 20:35
SEA
-
BHD
16h 15m
1 stop
£604British Airways
Thu, 24 Sep - Sun, 27 Sep
British Airways Logo
06:30 - 17:10
BHD
-
SEA
18h 40m
2 stops
British Airways Logo
06:15 - 10:30
SEA
-
BHD
20h 15m
2 stops
£609British Airways
Thu, 3 Dec - Mon, 7 Dec
British Airways Logo
07:00 - 16:55
BHD
-
SEA
17h 55m
2 stops
British Airways Logo
11:22 - 14:15
SEA
-
BHD
18h 53m
2 stops
£629British Airways
Thu, 16 Jul - Wed, 22 Jul
Multiple Airlines Logo
08:20 - 21:00
BFS
-
SEA
44h 40m
3 stops
Multiple Airlines Logo
15:40 - 22:20
SEA
-
BFS
22h 40m
3 stops
£652Multiple Airlines
Thu, 10 Sep - Thu, 1 Oct
KLM Logo
09:50 - 23:20
BHD
-
SEA
21h 30m
2 stops
KLM Logo
20:59 - 16:55
SEA
-
BHD
35h 56m
2 stops
£700KLM
Thu, 10 Sep - Thu, 1 Oct
Delta Logo
09:50 - 23:55
BHD
-
SEA
22h 05m
2 stops
Delta Logo
07:15 - 09:20
SEA
-
BHD
18h 05m
2 stops
£704Delta
Thu, 10 Sep - Thu, 1 Oct
Multiple Airlines Logo
06:10 - 20:40
BFS
-
SEA
22h 30m
2 stops
Multiple Airlines Logo
19:00 - 23:05
SEA
-
BFS
20h 05m
2 stops
£713Multiple 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 5 days.

In the past 3 days, the cheapest return tickets from Belfast to Seattle were found on British Airways (£556) and KLM (£700).

Good to know - Cheap tickets from Belfast to Seattle

Cheapest flight£507
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 £507 for a one-way ticket and £556 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 11768 reviews
7.9Crew
6.4Food
7.5Boarding
6.8Entertainment
7.2Comfort
Airline reviews

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

6.0 GoodDeannia, Mar 2026
PHL - SEA
Read more American Airlines reviews

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

Beverage service was not good. Also just one service in 5 hr 30 min flight. No ask fir water ir anything beside one time beverage service.

Flight was delayed because of a bird strike. They had another plane available within 45 minutes.

It was a code share with Alaska - would have been great if I actually made it on the plane, claimed I didn’t have a ticket or a seat even thought I was checked in.

The main problem was delay. The plane was at the gate early and bags were loaded. However, there was no crew for the flight. They were inbound from LGA and had to land and make their way to our gate. It took more than 40 minutes. Then, once the crew arrived and boarded, one of the crew members had to deplane and then a replacement crew member had to be found. It took another 40 minutes or so to get the final crew member. In all, we took off about 2 hours later than our scheduled departure time. Once in the air, the flight was great. Smooth most of the way. The crew was professional and efficient.

i suspect i caught flu on this flight as i could hear someone coughing a few rows back and ended up with flu a few days later. also tiresome to have to watch movies on my device by holding up smartphone screen, would have liked to have in seat display.

I had trouble finding a boarding pass because I had an hour between Flights and American did not see my flight I believe because I was ticketed through KAYAK. I did not have enough time to go to the desk before boarding so I went to the desk and told them while I was boarding and they had a boarding pass for me within three minutes. Nice. I paid extra to have more legroom and it is definitely worth it for a six hour flight. I would’ve paid for a decent dinner, but they didn’t offer anything but a snack box —not good for six hours.

Terrible flight seats where really uncomfortable I had body aches for 2 days and flight was delays almost two hours

Customer service prior to boarding is horrible Communication regarding boarding gates is released at the last minute and the gates are very distant from Customs. Very disappointing

the entertainment center did not work, upon request of resetting the device by me for 3 times. the device refused to work. the flight crew was not apologetic and did not offer any other solutions. such as moving me to another seat to accomodate their problem.

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

Information on your arrival and departure airports