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.

$628 Cheap Flights from Belfast Intl Airport to Seattle in 2026

1 adult

0 bags

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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.

9:40 pm - 9:40 am

BFS

SEA

44h 00m

3 stops

10:45 am - 11:25 pm

SEA

BFS

28h 40m

3 stops

$1,407Multiple Airlines

Sat, Jun 20 - Sat, Jun 27

9:40 pm - 9:40 am

BFS

SEA

44h 00m

3 stops

7:10 pm - 8:50 pm

SEA

BFS

17h 40m

2 stops

$1,432Multiple Airlines

Sat, Jun 20 - Sat, Jun 27

10:10 am - 1:45 pm

BFS

SEA

35h 35m

2 stops

3:55 pm - 10:15 pm

SEA

BFS

22h 20m

2 stops

$1,443Multiple Airlines

Sat, Jun 20 - Sat, Jun 27

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

Cheapest round-trip

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Sat 6/20

9:40 pm-9:40 am

3 stops44h 00m

Seattle/Tacoma Intl

Sat 6/27

10:45 am-11:25 pm

3 stops28h 40m

$1,407

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Sat 6/20

9:40 pm-9:40 am

3 stops44h 00m

Seattle/Tacoma Intl

Sat 6/27

7:10 pm-8:50 pm

2 stops17h 40m

$1,432

Quickest round-trip

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Sat 6/20

10:10 am-1:45 pm

2 stops35h 35m

Seattle/Tacoma Intl

Sat 6/27

3:55 pm-10:15 pm

2 stops22h 20m

$1,443

Cheapest one-way

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 8/24

9:05 pm-5:10 pm

3 stops28h 05m

$576

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 8/6

6:40 am-6:45 pm

3 stops44h 05m

$628

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Sun 7/5

10:10 pm-6:45 pm

3 stops52h 35m

$648

Quickest one-way

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Tue 8/25

8:20 am-5:55 pm

2 stops17h 35m

$654

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 8/24

6:10 am-8:40 pm

2 stops22h 30m

$708

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 8/6

6:40 am-6:45 pm

2 stops20h 05m

$802

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Sun 7/5

9:35 am-5:10 pm

2 stops39h 35m

$852

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	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.

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. 13h 05m 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

Lynnwood

Redmond

Kent

Tukwila

Puyallup

Marysville

Lakewood

Cle Elum

Federal Way

Centralia

Fife

Westport

Shoreline

Tumwater

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.