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

Price Alerts will notify you by email when the price for flights to Seattle from Belfast Intl Airport decreases. To activate this, select your desired travel dates and search for offers. While browsing through offers you’ll see the Price Alert widget toggle. Click it to turn on notifications.

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

Leverage our AI within our “Price Forecast” tool, which predicts if it’s better to book now or wait until prices decrease. You can strategically pick the best days to fly and save money on your trip by using our “Price Calendar” tool. “Explore” shows an overview of how much it costs to fly to anywhere from a selected city or airport. Our “Discover” content is a great option for travel inspiration and money-saving tips, while “Price Alerts” will update you when prices change, so you can book when fares are right.

How does momondo find its flight prices?

We aggregate our prices from over 700+ competitors from airlines to OTAs. We operate in over 30 markets worldwide to show you a wide range of travel options.

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.

$797 Cheap Flights from Belfast Intl Airport to Seattle in 2026

Find the cheapest flights from Belfast Intl Airport to Seattle

Round-trip

One-way

Cheap round-trip flights

Enter your travel dates to find the best prices.

9:00 am - 8:40 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

19h 40m2 stops London Luton Reykjavik Keflavik Intl

3:40 pm - 11:10 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

23h 30m2 stops Reykjavik Keflavik Intl London Gatwick

$797Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

9:00 am - 8:40 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

19h 40m2 stops London Luton Reykjavik Keflavik Intl

3:40 pm - 10:00 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

22h 20m2 stops Reykjavik Keflavik Intl London Heathrow

$800Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

9:00 am - 8:10 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

19h 10m1 stop London Luton

9:50 pm - 11:10 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

17h 20m1 stop London Heathrow

$840Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

8:20 am - 9:00 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

20h 40m3 stops Glasgow Intl Toronto Pearson Intl Calgary

3:40 pm - 8:40 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

21h 00m2 stops Reykjavik Keflavik Intl Glasgow Intl

$988Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

6:10 am - 6:45 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

44h 35m3 stops London Gatwick Toronto Pearson Intl Calgary

3:40 pm - 11:20 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

23h 40m3 stops Reykjavik Keflavik Intl Milan Malpensa London Stansted

$1,030Multiple Airlines

Thu, Sep 3 - Fri, Sep 11

8:40 pm - 8:40 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

32h 00m2 stops London Stansted Reykjavik Keflavik Intl

9:40 pm - 11:20 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

17h 40m1 stop London Heathrow

$1,081Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

9:05 pm - 9:07 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

32h 02m3 stops Edinburgh Turnhouse Halifax Intl Toronto Pearson Intl

3:40 pm - 11:20 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

23h 40m3 stops Reykjavik Keflavik Intl Kastrup Copenhagen London Stansted

$1,097Multiple Airlines

Thu, Sep 3 - Fri, Sep 11

8:20 am - 9:00 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

20h 40m3 stops Glasgow Intl Toronto Pearson Intl Calgary

7:00 pm - 11:20 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

20h 20m2 stops Reykjavik Keflavik Intl London Gatwick

$1,104Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

9:15 am - 8:40 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

19h 25m2 stops London Stansted Reykjavik Keflavik Intl

9:40 pm - 8:25 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

14h 45m1 stop London Heathrow

$1,114Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

8:20 am - 9:00 pmBFS Belfast Intl-SEA Seattle/Tacoma Intl

20h 40m3 stops Glasgow Intl Toronto Pearson Intl Calgary

3:40 pm - 11:05 pmSEA Seattle/Tacoma Intl-BFS Belfast Intl

23h 25m3 stops Reykjavik Keflavik Intl London Gatwick Edinburgh Turnhouse

$1,154Multiple Airlines

Thu, Sep 3 - Mon, Sep 7

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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 round-trip

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

9:00 am-8:40 pm

2 stops19h 40m

Seattle/Tacoma Intl

Mon 9/7

3:40 pm-11:10 pm

2 stops23h 30m

$797

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

9:00 am-8:40 pm

2 stops19h 40m

Seattle/Tacoma Intl

Mon 9/7

3:40 pm-10:00 pm

2 stops22h 20m

$800

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

9:00 am-8:10 pm

1 stop19h 10m

Seattle/Tacoma Intl

Mon 9/7

9:50 pm-11:10 pm

1 stop17h 20m

$840

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

8:20 am-9:00 pm

3 stops20h 40m

Seattle/Tacoma Intl

Mon 9/7

3:40 pm-8:40 pm

2 stops21h 00m

$988

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

6:10 am-6:45 pm

3 stops44h 35m

Seattle/Tacoma Intl

Fri 9/11

3:40 pm-11:20 pm

3 stops23h 40m

$1,030

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

8:40 pm-8:40 pm

2 stops32h 00m

Seattle/Tacoma Intl

Mon 9/7

9:40 pm-11:20 pm

1 stop17h 40m

$1,081

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

9:05 pm-9:07 pm

3 stops32h 02m

Seattle/Tacoma Intl

Fri 9/11

3:40 pm-11:20 pm

3 stops23h 40m

$1,097

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

8:20 am-9:00 pm

3 stops20h 40m

Seattle/Tacoma Intl

Mon 9/7

7:00 pm-11:20 pm

2 stops20h 20m

$1,104

Quickest round-trip

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

9:15 am-8:40 pm

2 stops19h 25m

Seattle/Tacoma Intl

Mon 9/7

9:40 pm-8:25 pm

1 stop14h 45m

$1,114

BelfastSeattle

BFS Belfast Intl - SEA Seattle/Tacoma Intl

BFSSEA

Belfast Intl

Thu 9/3

8:20 am-9:00 pm

3 stops20h 40m

Seattle/Tacoma Intl

Mon 9/7

3:40 pm-11:05 pm

3 stops23h 25m

$1,154

Flights are sorted by cheapest round-trip 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 round-trip 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 55m
Direct flights	None

The fastest flight from Belfast Intl Airport to Seattle takes 12h 55m

There are no direct flights from Belfast Intl Airport to Seattle. There are no popular flight routes from Belfast Intl Airport to Seattle.

Search flight deals

Frequently asked questions about flying from Belfast Intl Airport to Seattle

How far is Belfast Intl to Seattle/Tacoma Intl by plane?
The straight-line distance from Belfast Intl to Seattle/Tacoma Intl is 4452.2 mi. 12h 55m is a normal flight duration for this route.
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?
Price Alerts will notify you by email when the price for flights to Seattle from Belfast Intl Airport decreases. To activate this, select your desired travel dates and search for offers. While browsing through offers you’ll see the Price Alert widget toggle. Click it to turn on notifications.
How can I save money on flights from Belfast Intl Airport to Seattle with momondo?
Leverage our AI within our “Price Forecast” tool, which predicts if it’s better to book now or wait until prices decrease. You can strategically pick the best days to fly and save money on your trip by using our “Price Calendar” tool. “Explore” shows an overview of how much it costs to fly to anywhere from a selected city or airport. Our “Discover” content is a great option for travel inspiration and money-saving tips, while “Price Alerts” will update you when prices change, so you can book when fares are right.
How does momondo find its flight prices?
We aggregate our prices from over 700+ competitors from airlines to OTAs. We operate in over 30 markets worldwide to show you a wide range of travel options.

Tacoma

Leavenworth

SeaTac

Ocean Shores

Renton

Olympia

Kent

Lynnwood

Redmond

Lakewood

Puyallup

Fife

Federal Way

Tukwila

Cle Elum

Marysville

Kirkland

Centralia

Shoreline

Lacey

Why use momondo?

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

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Belfast to Seattle. momondo saves you time and could save you money on your trip.

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

momondo does allow users to show only those flights to Seattle from Belfast which offer a flexible booking policy as well as other useful filters and features.

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

momondo helps you find the best flight between Belfast and Seattle by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

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.