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Cheap flights from Belfast Intl Airport to Seattle from £461

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Belfast Intl Airport to Seattle departing on 27/8. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

Find the cheapest flights from Belfast Intl Airport to Seattle

Cheap return flights

Enter your travel dates to find the best prices.
Multiple Airlines Logo
06:10 - 09:40BFS  Belfast Intl-SEA Seattle/Tacoma Intl
35h 30m3 stops London Gatwick Montreal Pierre Elliott Trudeau Intl Calgary
Multiple Airlines Logo
15:40 - 23:20SEA  Seattle/Tacoma Intl-BFS Belfast Intl
23h 40m3 stops Reykjavik Keflavik Intl Milan Malpensa London Stansted
£767Multiple Airlines
Mon, 7 Sep - Fri, 11 Sep
Multiple Airlines Logo
10:05 - 16:35BFS  Belfast Intl-SEA Seattle/Tacoma Intl
14h 30m1 stop Amsterdam Schiphol
Multiple Airlines Logo
13:50 - 12:00SEA  Seattle/Tacoma Intl-BFS Belfast Intl
14h 10m2 stops Amsterdam Schiphol Liverpool J. Lennon
£1,950Multiple Airlines
Mon, 7 Sep - Fri, 11 Sep

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Customise your flight search to find flights from Belfast Intl Airport to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 279,928 searches. Data last updated 12 August 2026.
Use the filters below to find and compare flights from Belfast Intl Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Mon 7/9

06:10-09:40

3 stops35h 30m

Seattle/Tacoma Intl

Fri 11/9

15:40-23:20

3 stops23h 40m

£767
Fastest return journey

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Mon 7/9

10:05-16:35

1 stop14h 30m

Seattle/Tacoma Intl

Fri 11/9

13:50-12:00

2 stops14h 10m

£1,950
Cheapest one-way

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 27/8

06:10-09:19

3 stops35h 09m

£461

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Wed 26/8

22:45-18:45

3 stops52h 00m

£464

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Sun 3/1

07:50-17:00

2 stops41h 10m

£495

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Wed 26/8

07:30-11:45

2 stops36h 15m

£551

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 27/8

19:40-19:13

2 stops31h 33m

£552
Fastest single journey

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Sun 3/1

22:00-17:00

3 stops27h 00m

£578

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Mon 14/9

20:55-17:55

2 stops53h 00m

£587

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Mon 14/9

19:35-19:00

1 stop31h 25m

£757

Flights are sorted by cheapest return flights first.

Sorted by cheapest first

When to book flights from Belfast Intl Airport to Seattle

Are you open to changing your travel dates? Check out the ideal times to fly from Belfast Intl Airport to Seattle according to our flight data. Find out which month and days have the cheapest flights.
Estimated return price

Cheap Belfast Intl Airport to Seattle (BFS to SEA) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Belfast Intl Airport to Seattle

Fastest flight time

13h 05m

Direct flights

None
The fastest flight from Belfast Intl Airport to Seattle takes 13h 05m
There are no direct flights from Belfast Intl Airport to Seattle. There are no popular flight routes from Belfast Intl Airport to Seattle.
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Frequently asked questions about flying from Belfast Intl Airport to Seattle

  • How far is Belfast Intl to Seattle/Tacoma Intl by plane?

    Belfast Intl and Seattle/Tacoma Intl are 4452.2 mi apart from one another. Flights usually cover this in 13h 05m, depending on flying conditions and air traffic around both airports.

  • When did momondo last update prices for flights from Belfast Intl Airport to Seattle/Tacoma Intl Airport?

    Prices for flights from Belfast Intl Airport to Seattle/Tacoma Intl Airport were last updated today.

  • How old do you have to be to fly from Belfast Intl Airport to Seattle/Tacoma Intl Airport?

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Belfast Intl Airport to Seattle/Tacoma Intl Airport.

  • What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

    The necessary travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

Frequently asked questions about flying from Belfast Intl Airport to Seattle

  • How do I get Price Alerts for flights from Belfast Intl Airport to Seattle?

    Confirm your travel details to search for the latest offers for flights from Belfast Intl Airport to Seattle. While browsing offers there will be the option to toggle “Price Alerts”. You’ll then receive updates when prices for the flight route increase or decrease.

  • How can I save money on flights from Belfast Intl Airport to Seattle with momondo?

    Plan your trips smart with the “Price Forecast” feature, which uses flight data to help you pick the best days to fly for the lowest fares. Our “Price Calendar” helps you get the most for your money by showing you when it’s most advantageous to fly. Curate your own travel experiences for less with “Explore”. Expert travel hacks to fuel your next adventure are a click away with “Discover” by momondo. Set up our “Price Alerts” to track fare changes and book when prices are at their lowest point.

  • How does momondo find its flight prices?

    momondo shows deals across 700+ competitors all at once. momondo is active in 30 international markets, so you can have access to a wide range of options from airlines and OTAs alike.

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Westport
Kirkland
Ashford
Tacoma
SeaTac
Tukwila
Fife

Why use momondo?

Why should I use momondo to find a flight deal from Belfast to Seattle?

Finding the right flight to Seattle from Belfast is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Seattle quick and easy, saving you time and money.

Can I find flights from Belfast to Seattle with flexible booking policies on momondo?

Yes. All flights to Seattle from Belfast on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Belfast to Seattle?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Belfast to Seattle.

I’m not ready to book a flight from Belfast to Seattle right now. Can momondo alert me if prices change?

If you are not ready to book a flight from Belfast to Seattle now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Seattle and let you know when they change.

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