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.

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 many operators does momondo search for flights from Belfast Intl Airport to Seattle/Tacoma Intl Airport?

There are 2 operators available for flights from Belfast Intl Airport to Seattle/Tacoma Intl Airport as of August 2025.

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.

£545 Cheap Flights from Belfast Intl Airport to Seattle in 2025

1 adult

0 bags

Discover deals from 900+ travel sites with momondo.

Voted winner of Europe's Best Travel App 2023

Save money when you book flights with momondo

Big names, great deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Stopover? Instantly customise your results.

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

Find the cheapest flights from Belfast Intl Airport to Seattle

Round-trip

One-way

Last minute

Cheap return flights

06:35 - 20:40BFS-SEA

22h 05m2 stops

19:00 - 23:10SEA-BFS

20h 10m2 stops

£607

Find Deal

jeu., 4 sept. - mer., 10 sept.

06:35 - 10:15BFS-SEA

35h 40m2 stops

17:35 - 20:30SEA-BFS

18h 55m1 stop

£697

Find Deal

jeu., 4 sept. - mer., 10 sept.

14:50 - 20:29BFS-SEA

37h 39m2 stops

13:50 - 14:05SEA-BFS

16h 15m2 stops

£1,095

Find Deal

mar., 14 oct. - jeu., 23 oct.

momondo Fare Finder

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

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

jeu. 4/9

06:35-20:40

2 stops22h 05m

Seattle/Tacoma Intl

mer. 10/9

19:00-23:10

2 stops20h 10m

£607

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

jeu. 4/9

06:35-10:15

2 stops35h 40m

Seattle/Tacoma Intl

mer. 10/9

17:35-20:30

1 stop18h 55m

£697

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

mar. 14/10

14:50-20:29

2 stops37h 39m

Seattle/Tacoma Intl

jeu. 23/10

13:50-14:05

2 stops16h 15m

£1,095

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

Best price found	£607
Fastest flight time	22h 05m
Direct flights	None
Airports in Seattle	1 airport

The best flight deal from Belfast Intl Airport to Seattle found on momondo in the last 72 hours is £607

The fastest flight from Belfast Intl Airport to Seattle takes 22h 05m

There are no direct flights from Belfast Intl Airport to Seattle. Popular non-direct route for this connection is Belfast Intl Airport - Seattle/Tacoma Intl Airport.

There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)

Search flight deals

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 22h 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 many operators does momondo search for flights from Belfast Intl Airport to Seattle/Tacoma Intl Airport?
There are 2 operators available for flights from Belfast Intl Airport to Seattle/Tacoma Intl Airport as of August 2025.
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.
What is the most popular airline from Belfast Intl Airport to Seattle?
momondo data reveals that the most frequently booked airline on the route from Belfast Intl Airport to Seattle is British Airways, representing 74% of all bookings. The subsequent popular airline is American Airlines at 26%.

Best airlines flying from Belfast Intl Airport to Seattle

Compare and see reviews for airlines that fly from Belfast Intl Airport to Seattle with momondo

Airline	Rating	Free Cancellation	Price
British Airways	PriceFrom £445	Free Cancellation	Rating 6.6 7,222 reviews		Search British Airways flights
American Airlines	PriceFrom £567	Free Cancellation	Rating 7.2 10,000 reviews		Search American Airlines flights

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.

Kent

SeaTac

Fife

Tukwila

Renton

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.