SEA

£390 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 7/9. 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
Travellers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 27% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Everything you should know

Cheapest return fare
£554
British Airways
Wed 16/9Wed 7/10
BHD - SEA • 1 stop
Cheapest one-way flight
£390
Multiple Airlines
Mon 7/9
BFS - SEA • 3 stops
Top airlines
Cheapest • from £554 (return)
Best reviews • 7.1 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Start a new search
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, 16 Sep - Wed, 7 Oct
British Airways Logo
20:35 - 11:35
BHD
-
SEA
23h 00m
1 stop
British Airways Logo
11:34 - 12:00
SEA
-
BHD
16h 26m
2 stops
£554British Airways
Wed, 23 Sep - Wed, 14 Oct
British Airways Logo
20:35 - 11:35
BHD
-
SEA
23h 00m
1 stop
British Airways Logo
13:30 - 12:00
SEA
-
BHD
14h 30m
1 stop
£555British Airways
Wed, 23 Sep - Wed, 14 Oct
British Airways Logo
20:35 - 11:35
BHD
-
SEA
23h 00m
1 stop
British Airways Logo
20:20 - 19:50
SEA
-
BHD
15h 30m
1 stop
£575British Airways
Wed, 23 Sep - Wed, 14 Oct
British Airways Logo
20:35 - 11:35
BHD
-
SEA
23h 00m
1 stop
British Airways Logo
20:20 - 19:50
SEA
-
BHD
15h 30m
1 stop
£582British Airways
Wed, 16 Sep - Wed, 7 Oct
British Airways Logo
10:05 - 21:36
BHD
-
SEA
19h 31m
2 stops
British Airways Logo
11:34 - 12:00
SEA
-
BHD
16h 26m
2 stops
£585British Airways
Wed, 23 Sep - Wed, 14 Oct
KLM Logo
17:30 - 11:47
BHD
-
SEA
26h 17m
1 stop
KLM Logo
09:30 - 09:20
SEA
-
BHD
15h 50m
2 stops
£591KLM
Wed, 23 Sep - Wed, 14 Oct
KLM Logo
09:50 - 11:47
BHD
-
SEA
33h 57m
1 stop
KLM Logo
17:45 - 16:55
SEA
-
BHD
15h 10m
2 stops
£597KLM
Wed, 23 Sep - Wed, 14 Oct
Delta Logo
09:50 - 18:55
BHD
-
SEA
17h 05m
2 stops
Delta Logo
07:30 - 09:20
SEA
-
BHD
17h 50m
2 stops
£597Delta
Wed, 16 Sep - Wed, 7 Oct
Multiple Airlines Logo
20:15 - 20:40
BFS
-
SEA
32h 25m
3 stops
Multiple Airlines Logo
15:40 - 20:15
SEA
-
BFS
20h 35m
3 stops
£721Multiple Airlines
Wed, 16 Sep - Wed, 7 Oct
Multiple Airlines Logo
09:35 - 09:40
BFS
-
SEA
32h 05m
2 stops
Multiple Airlines Logo
15:40 - 20:15
SEA
-
BFS
20h 35m
3 stops
£768Multiple 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 (£554) and KLM (£591).

Good to know - Cheap tickets from Belfast to Seattle

Cheapest flight£390
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 £390 for a one-way ticket and £554 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 11739 reviews
7.9Crew
7.5Boarding
7.2Comfort
6.8Entertainment
6.4Food
Airline reviews

Rudest flight attendants ever, waited over 20 for light to be answered and it never was then tried to flag down an attendant who said someone else would come, just needed water to take some medicine Food bad

4.0 OkayLisa, Jun 2026
LHR - PHL
Read more American Airlines reviews

Rudest flight attendants ever, waited over 20 for light to be answered and it never was then tried to flag down an attendant who said someone else would come, just needed water to take some medicine Food bad

My entertainment unit kept locking up and had to be restarted multiple times. Also those commercials for Budapest and Ralph Laureen. Come on those were stuff only those who can afford the outrageous fees of first and business class would be interested in.. And the fact you have no military discount is not good either,

I was a Wheelchair Assist’ passenger on a London Heathrow to PHL flight yesterday. The process of getting me and my carry-on bag from the ticket counter to the gate was not good at all. It was the worst in my 5 years of experience using this service offered by American. The Philadelphia ‘Wheelchair Assist’ service was, and always has been Excellent! Not so at Heathrow. I was handed off to three different wheelchair drivers; had to sit in a very dingy holding area for 30 minutes while waiting for our gate change announcement; got crammed into a overloaded service vehicle to take me from the holding area to the gate ; was dumped at the end of the line of already-boarding passengers with my heavy carryon and no one helped me up the ramp way at the gate to board the plane. Overall it was a miserable experience!

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..

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

Information on your arrival and departure airports