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Belfast Intl

$291+ Cheap flights from Seattle (SEA) to Belfast Intl (BFS)

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 7/18. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BFS
Apr 9 — Apr 161
Thu 4/9
Thu 4/16
1 adult, Economy
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Cheap flight deals from Seattle to Belfast Intl

Cheapest flights from Seattle to Belfast Intl
Explore the most affordable flight options available from Seattle to Belfast Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 10, 2026.

This Mytrip deal was found by Cheapflights users on 3/7. 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 4/213:40 pm
SEA
-
BFS
2 stops15h 35m
Multiple Airlines
Tue 4/287:35 am
BFS
-
SEA
2 stops18h 20m
Multiple Airlines
Deal found 3/7$659
This Mytrip deal was found by Cheapflights users on 3/6. 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.
Mon 4/133:40 pm
SEA
-
BFS
3 stops23h 40m
Multiple Airlines
Mon 4/206:10 am
BFS
-
SEA
3 stops45h 13m
Multiple Airlines
Deal found 3/6$816
This Mytrip deal was found by Cheapflights users on 3/6. 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.
Wed 4/223:40 pm
SEA
-
BFS
3 stops22h 40m
Multiple Airlines
Sun 4/268:25 pm
BFS
-
SEA
3 stops45h 15m
Multiple Airlines
Deal found 3/6$861
This Mytrip deal was found by Cheapflights users on 3/7. 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 5/287:00 pm
SEA
-
BFS
2 stops20h 05m
Multiple Airlines
Mon 6/18:40 am
BFS
-
SEA
3 stops39h 20m
Multiple Airlines
Deal found 3/7$873
This Mytrip deal was found by Cheapflights users on 3/9. 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 8/43:40 pm
SEA
-
BFS
2 stops15h 35m
Multiple Airlines
Wed 8/128:30 am
BFS
-
SEA
3 stops40h 40m
Multiple Airlines
Deal found 3/9$949
This Mytrip deal was found by Cheapflights users on 3/9. 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.
Mon 8/34:35 pm
SEA
-
BFS
2 stops20h 20m
Multiple Airlines
Tue 8/184:40 pm
BFS
-
SEA
3 stops32h 30m
Multiple Airlines
Deal found 3/9$988
This Mytrip deal was found by Cheapflights users on 3/9. 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.
Wed 8/55:40 am
SEA
-
BFS
3 stops29h 35m
Multiple Airlines
Tue 8/184:40 pm
BFS
-
SEA
3 stops32h 30m
Multiple Airlines
Deal found 3/9$1,036

Find flight deals from Seattle to Belfast Intl

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Belfast Intl (BFS). 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 March 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$659
(Mytrip)

One-way from

$291
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$822
Provider with most accurate pricing for Seattle/Tacoma Intl-Belfast Intl flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Belfast Intl flights.
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From Seattle/Tacoma Intl to Belfast Intl
Search Deals
One-way flight from Seattle/Tacoma Intl to Belfast Intl
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($182 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($57 potential savings vs. average RT price).
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Average for round-trip flights in March 2026
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Belfast Intl 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 March 10, 2026.
Use the filters below to find and compare flights from Seattle to Belfast Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Wed 4/22

3:40 pm-10:20 pm

3 stops22h 40m

Belfast Intl

Sun 4/26

8:25 pm-9:40 am

3 stops45h 15m

$861

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 5/28

7:00 pm-11:05 pm

2 stops20h 05m

Belfast Intl

Mon 6/1

8:40 am-4:00 pm

3 stops39h 20m

$873
Quickest round-trip

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 4/13

3:40 pm-11:20 pm

3 stops23h 40m

Belfast Intl

Mon 4/20

8:15 am-8:40 pm

2 stops20h 25m

$879

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sat 8/1

3:40 pm-8:40 pm

2 stops21h 00m

Belfast Intl

Mon 8/17

8:40 am-5:10 pm

3 stops40h 30m

$1,058

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 8/6

7:10 pm-7:30 pm

2 stops16h 20m

Belfast Intl

Tue 8/18

4:40 pm-5:10 pm

3 stops32h 30m

$1,100

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sat 8/1

5:40 am-9:35 am

3 stops19h 55m

Belfast Intl

Thu 8/13

9:15 am-5:10 pm

3 stops39h 55m

$1,119

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 8/7

5:40 am-4:30 pm

3 stops26h 50m

Belfast Intl

Thu 8/13

9:15 am-5:10 pm

3 stops39h 55m

$1,178

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 7/7

8:00 am-3:15 pm

2 stops23h 15m

Belfast Intl

Sat 7/18

9:40 pm-11:45 am

2 stops22h 05m

$1,256
Cheapest one-way

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sat 7/18

3:40 pm-8:15 am

2 stops32h 35m

$291

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sun 7/12

3:40 pm-10:00 am

2 stops34h 20m

$320

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/9

Showing 1-10 of 14 resultsSorted by cheapest first
1
2

Compare providers for flights from Seattle to Belfast Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Belfast Intl in March.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Belfast Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Belfast Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Belfast Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Belfast Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Belfast Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Seattle to Belfast Intl

Have a flexible travel schedule? Discover the best time to fly to Belfast Intl 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.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Belfast Intl. 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 Intl?

    Located just 11.4 mi from the city center, Seattle/Tacoma Intl is the airport most travelers will use when flying to Belfast Intl from Seattle. Booking flights from Seattle/Tacoma Intl (SEA) to Belfast Intl should be relatively easy as there are 0 daily outbound flights to Belfast Intl from 0 different airlines.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Seattle to Belfast Intl 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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Other flights to Belfast Intl

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