BFS - SEA

Find Cheap Flights from Belfast Intl Airport to Seattle

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

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Everything you should know

Cheapest return fare
Multiple Airlines
Sat 31/1
BFS - SEA • multi-stop
Cheapest one-way flight
Multiple Airlines
Sat 31/1
BFS - SEA • multi-stop
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We hope you love your trip to Seattle!
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Booking Insights
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

Multiple Airlines Logo
BFS
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SEA
4461 mimulti-stop
Multiple Airlines Logo
SEA
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BFS
4461 mimulti-stop
Multiple Airlines
Booking Insights

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

  • 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.

  • Which is the best airline for flights from Belfast to Seattle, American Airlines or British Airways?

    The two airlines most popular with KAYAK users for flights from Belfast to Seattle are American Airlines and British Airways. With an average price for the route of £547 and an overall rating of 7.2, American Airlines is the most popular choice. British Airways is also a great choice for the route, with an average price of £694 and an overall rating of 6.7.

  • 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.
7.2
American AirlinesOverall score based on 11213 reviews
7.5Boarding
7.2Comfort
6.9Entertainment
8.0Crew
6.4Food
Airline reviews

Update to handle the delay was very bad, crews no smiles or welcome or thanks. Don’t care attitude

2.0 MediocreManikandan, Jan 2026
DFW - ORD
Read more American Airlines reviews

Update to handle the delay was very bad, crews no smiles or welcome or thanks. Don’t care attitude

It would be nice to have some low carb options in the snacks.

I was trying to take 2 one and a half hour one way trips and I experienced almost 20 delays over the course of those two trips. Only a few of them were due to weather the rest was disorganization

Crew was clearly not loving their jobs at any point of the entire trip. Flight back from Mexico, I asked if they had food for sale for the 2.5+hr flight and they did not have any. The business class trip to Mexico also had noted that the catering company forgot to load food. The last leg of trip back had a similarly unhappy crew, a broken toilet, and my seat was broken (reclining would not lock which made landing a crossfit like event). This was a bad week for AA.

No gates avail at DFW so our incoming had to wait 30 mins for a plane to push back because they Had mechanical. We boarded 90 mins delayed and then we had a mechanical. Come on American…do better. Also at my seat the tray table had not been cleaned. Floor had not been cleaned. But captain and flight Att were very picture and apologetic.

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.

The business class seats are dated and uncomfortable. The space is bare minimum and there is absolutely no privacy. For $4K, this is not what I expect.

Flight, food and crew were all good, friendly and very satisfactory.

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

Information on your arrival and departure airports

Belfast Intl Airport (BFS)
Seattle (SEA)