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 December 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.

£630 Cheap Flights from Belfast Intl Airport to Seattle in 2025/26

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Multiple Airlines

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	12h 30m
Direct flights	None

The fastest flight from Belfast Intl Airport to Seattle takes 12h 30m

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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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 12h 30m, 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 December 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 £440	Free Cancellation	Rating 6.7 7,575 reviews		Search British Airways flights
American Airlines	PriceFrom £561	Free Cancellation	Rating 7.2 11,051 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.

Fife

Renton

SeaTac

Tukwila

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.