SEA

£672 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 7/3. 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
£672
Multiple Airlines
Sat 11/4Sat 18/4
BFS - SEA • 2 stops
Cheapest one-way flight
£412
Multiple Airlines
Sat 7/3
BFS - SEA • 3 stops
Top airlines
KLM
Cheapest • from £770 (return)
American Airlines
Best reviews • 7.2 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

Sat, 11 Apr - Sat, 18 Apr
Multiple Airlines Logo
07:00 - 16:00
BFS
-
SEA
17h 00m
2 stops
Multiple Airlines Logo
15:40 - 22:40
SEA
-
BFS
23h 00m
3 stops
£672Multiple Airlines
Tue, 9 Jun - Sat, 20 Jun
Multiple Airlines Logo
10:20 - 20:40
BHD
-
SEA
18h 20m
2 stops
Multiple Airlines Logo
17:40 - 09:20
SEA
-
BHD
31h 40m
1 stop
£733Multiple Airlines
Sat, 11 Apr - Sat, 18 Apr
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
£741Multiple Airlines
Tue, 7 Jul - Fri, 17 Jul
KLM Logo
17:30 - 11:15
BHD
-
SEA
25h 45m
2 stops
KLM Logo
09:30 - 09:20
SEA
-
BHD
15h 50m
2 stops
£770KLM
Tue, 7 Jul - Fri, 17 Jul
British Airways Logo
09:40 - 22:58
BHD
-
SEA
21h 18m
2 stops
British Airways Logo
13:35 - 18:10
SEA
-
BHD
20h 35m
1 stop
£778British Airways
Tue, 9 Jun - Sat, 20 Jun
Multiple Airlines Logo
09:50 - 11:37
BHD
-
SEA
33h 47m
1 stop
Multiple Airlines Logo
17:40 - 09:20
SEA
-
BHD
31h 40m
1 stop
£806Multiple Airlines
Tue, 7 Jul - Fri, 17 Jul
Multiple Airlines Logo
17:30 - 11:33
BHD
-
SEA
26h 03m
1 stop
Multiple Airlines Logo
17:40 - 09:20
SEA
-
BHD
31h 40m
1 stop
£843Multiple Airlines
Tue, 9 Jun - Sat, 20 Jun
Aer Lingus Logo
19:30 - 17:10
BHD
-
SEA
29h 40m
2 stops
Aer Lingus Logo
19:10 - 20:55
SEA
-
BHD
17h 45m
2 stops
£895Aer Lingus
Sat, 11 Apr - Sat, 18 Apr
Multiple Airlines Logo
10:35 - 21:53
BFS
-
SEA
43h 18m
3 stops
Multiple Airlines Logo
15:40 - 22:40
SEA
-
BFS
23h 00m
3 stops
£944Multiple 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 KLM (£770) and British Airways (£778).

Good to know - Cheap tickets from Belfast to Seattle

Cheapest flight£412
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 £412 for a one-way ticket and £672 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.
7.2
American AirlinesOverall score based on 11357 reviews
8.0Crew
7.2Comfort
7.5Boarding
6.4Food
6.9Entertainment
Airline reviews

For my arriving destination, we were delayed multiple times to the point that we arrived 6 hours after we were originally scheduled. On my flight home, they overbooked and involuntarily removed passengers (including me) from the plane. It was not a good experience.

2.0 MediocreHannah, Feb 2026
PBI - CLT
Read more American Airlines reviews

For my arriving destination, we were delayed multiple times to the point that we arrived 6 hours after we were originally scheduled. On my flight home, they overbooked and involuntarily removed passengers (including me) from the plane. It was not a good experience.

It was good experience this time. The flight was on time.

I very rarely fly American and my experience today reenforces that is the correct decision. While the staff were all very courteous, our flight was first thing in the morning so there was no reason to be delayed, yet appropriate maintenance checks weren’t completed prior to our flight so we were delayed multiple times. Not a great showing, American Airlines.

It's very confusing because Kayak has it as American Airlines, but it was Hawaiian Airlines, but operated by Alaska Airlines. I had to go to the airport for my boarding pass because American said I didn't have any trips.

Smooth flight. From the early boarding and all were on board before departure time and arrived early in ONT. Great crew. Thank you!!!!

Small plane, poor meal choices for first class, bad terminal and boarding experience at LAX

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.

The flight attendant use 1.5 hours to answer my call. My dirty food tray was unattended.

The flight was completely full. Crew was not happy. Everyone was rude and brusque. Travelling with an arm in a cast and seating in the first row of economy cabin (in front of the separation) I needed help retrieving my tray for the meal. A staff member literally threw the tray on my lap, without helping to take out the tray. Boarding was messy, with 300 people waiting in an encloses space with low ceiling. I will try to avoid AA next time I have a long flight.

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

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

Information on your arrival and departure airports