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$349+ Cheap flights from Seattle (SEA) to Belfast

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/15. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BHD
May 1 — May 81
Fri 5/1
Fri 5/8
1 adult, Economy
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Cheap flight deals from Seattle to Belfast

Cheapest flights from Seattle to Belfast
Explore the most affordable flight options available from Seattle to Belfast. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 1, 2026.

This Cheapflightsfares deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/58:20 pm
SEA
-
BHD
1 stop14h 25m
British Airways
Thu 10/226:30 am
BHD
-
SEA
1 stop19h 55m
British Airways
Deal found 3/31$886
This British Airways deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/61:30 pm
SEA
-
BHD
1 stop13h 00m
British Airways
Thu 9/108:35 pm
BHD
-
SEA
1 stop23h 00m
British Airways
Deal found 3/31$905
This Iberia deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/53:10 pm
SEA
-
BHD
2 stops16h 20m
Multiple Airlines
Thu 10/2212:45 pm
BHD
-
SEA
1 stop13h 40m
Multiple Airlines
Deal found 3/31$909
This Cheapflightsfares deal was found by Cheapflights users on 3/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/148:20 pm
SEA
-
BHD
1 stop13h 10m
British Airways
Mon 9/217:35 pm
BHD
-
SEA
1 stop24h 00m
British Airways
Deal found 3/27$917
This Kiwi.com deal was found by Cheapflights users on 3/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/147:10 pm
SEA
-
BFS
2 stops27h 55m
Multiple Airlines
Mon 9/219:15 am
BFS
-
SEA
1 stop17h 40m
Multiple Airlines
Deal found 3/27$1,020
This Mytrip deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/102:10 pm
SEA
-
BFS
2 stops23h 30m
Multiple Airlines
Thu 9/179:25 pm
BFS
-
SEA
3 stops28h 30m
Multiple Airlines
Deal found 3/29$1,062
This Mytrip deal was found by Cheapflights users on 3/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/176:50 pm
SEA
-
BFS
3 stops20h 30m
Multiple Airlines
Sun 5/37:10 am
BFS
-
SEA
3 stops34h 30m
Multiple Airlines
Deal found 3/27$1,086
This Trip.com deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/147:00 pm
SEA
-
BFS
2 stops17h 35m
Multiple Airlines
Thu 5/216:10 am
BFS
-
SEA
2 stops22h 30m
Multiple Airlines
Deal found 3/30$1,197
This Mytrip deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/237:00 am
SEA
-
BFS
3 stops31h 15m
Multiple Airlines
Wed 7/15:55 am
BFS
-
SEA
3 stops20h 50m
Multiple Airlines
Deal found 3/29$1,211

Find flight deals from Seattle to Belfast

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Belfast (BF1). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated April 1, 2026.

Round-trip from

$905
(British Airways)

One-way from

$349
(Cheapflightsfares)

Popular in

December

Cheapest in

October

Average price

$868
From Seattle/Tacoma Intl to Belfast
Search Deals
One-way flight from Seattle/Tacoma Intl to Belfast
Search Deals
Highest demand for flights based on searches. 14% potential increase in price ($174 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($56 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Belfast 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, Cheapflights users made 2,558,603 searches. Data last updated April 1, 2026.
Use the filters below to find and compare flights from Seattle to Belfast that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 6/1

3:40 pm-11:10 pm

3 stops23h 30m

Belfast Intl

Mon 6/8

5:35 pm-9:08 pm

3 stops35h 33m

$845

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sun 9/6

1:30 pm-10:30 am

1 stop13h 00m

Belfast City

Thu 9/10

8:35 pm-11:35 am

1 stop23h 00m

$905
Quickest round-trip

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 9/10

8:20 pm-7:25 pm

1 stop15h 05m

Belfast City

Thu 9/17

6:30 am-6:25 pm

1 stop19h 55m

$935

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 9/14

7:10 pm-7:05 am

2 stops27h 55m

Belfast Intl

Mon 9/21

9:15 am-6:55 pm

1 stop17h 40m

$1,020

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 9/10

2:10 pm-9:40 pm

2 stops23h 30m

Belfast Intl

Thu 9/17

9:25 pm-5:55 pm

3 stops28h 30m

$1,062

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Mon 6/1

8:20 pm-5:30 pm

1 stop13h 10m

Belfast City

Mon 6/8

7:35 pm-11:35 am

1 stop24h 00m

$1,063

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 4/17

6:50 pm-11:20 pm

3 stops20h 30m

Belfast Intl

Sun 5/3

7:10 am-9:40 am

3 stops34h 30m

$1,086

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 4/16

1:30 pm-10:10 am

1 stop12h 40m

Belfast City

Sun 5/3

8:10 pm-11:35 am

1 stop23h 25m

$1,125

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 6/1

7:00 pm-8:25 pm

2 stops17h 25m

Belfast Intl

Tue 6/9

8:00 am-11:45 am

2 stops35h 45m

$1,138

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 6/23

7:00 am-10:15 pm

3 stops31h 15m

Belfast Intl

Wed 7/1

5:55 am-6:45 pm

3 stops20h 50m

$1,211

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/28

Showing 1-10 of 14 resultsSorted by cheapest first
1
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Best time to book a flight from Seattle to Belfast

Have a flexible travel schedule? Discover the best time to fly to Belfast from Seattle with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Seattle to Belfast

How much does it cost to fly round-trip from Seattle to Belfast?

Related info for your journey

Find useful and relevant information for your journey from Seattle to Belfast. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Seattle to Belfast?

    If you book a flight to Belfast from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 0 flights from Seattle/Tacoma Intl to Belfast per day from 0 different airlines.

  • How long is the flight from Seattle to Belfast?

    Airlines like British Airways fly from Seattle to Belfast in about 13h. The time it takes to get you to your destination can typically vary by up to . The distance between Seattle and Belfast is about 4472 mi.

  • Can I find deals for flights from Seattle to Belfast that include hotel bookings?

    Yes. In addition to deals on Seattle to Belfast flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to Belfast?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to Belfast.

  • Can I find deals for business class flights from Seattle to Belfast?

    Yes. Cheapflights offers flight deals from Seattle to Belfast by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

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Alternative routes for Seattle to Belfast

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Seattle to Belfast Intl flights

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