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$321+ 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 8/17. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BHD
Jun 11 — Jun 181
Thu 6/11
Thu 6/18
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 May 12, 2026.

This Cheapflightsfares deal was found by Cheapflights users on 5/7. 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 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 stop16h 15m
British Airways
Thu 10/2212:45 pm
BHD
-
SEA
1 stop13h 40m
British Airways
Deal found 5/7$891
This British Airways deal was found by Cheapflights users on 5/7. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/191:30 pm
SEA
-
BHD
1 stop15h 25m
British Airways
Wed 10/214:05 pm
BHD
-
SEA
1 stop34h 20m
British Airways
Deal found 5/7$909
This deal was found by Cheapflights users on 5/8. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/88:20 pm
SEA
-
BHD
1 stop14h 35m
British Airways
Fri 9/2511:00 am
BHD
-
SEA
1 stop15h 25m
British Airways
Deal found 5/8$910
This Iberia deal was found by Cheapflights users on 5/7. 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 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 10/226:30 am
BHD
-
SEA
1 stop13h 05m
Multiple Airlines
Deal found 5/7$914
This Iberia deal was found by Cheapflights users on 5/8. 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.
Tue 9/88:20 pm
SEA
-
BHD
1 stop14h 35m
Multiple Airlines
Tue 9/159:40 am
BHD
-
SEA
2 stops19h 29m
Multiple Airlines
Deal found 5/8$923
This FlightHub deal was found by Cheapflights users on 5/8. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/176:00 am
SEA
-
BHD
2 stops22h 55m
British Airways
Tue 8/257:30 pm
BHD
-
SEA
1 stop24h 05m
British Airways
Deal found 5/8$927
This Mytrip deal was found by Cheapflights users on 5/11. 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 5/283:40 pm
SEA
-
BFS
3 stops22h 00m
Multiple Airlines
Mon 6/16:30 am
BFS
-
SEA
3 stops44h 15m
Multiple Airlines
Deal found 5/11$935
This Cheapflightsfares deal was found by Cheapflights users on 5/9. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/81:30 pm
SEA
-
BHD
1 stop12h 40m
British Airways
Thu 10/226:30 am
BHD
-
SEA
1 stop13h 05m
British Airways
Deal found 5/9$939
This Mytrip deal was found by Cheapflights users on 5/10. 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 7/233:40 pm
SEA
-
BFS
2 stops22h 00m
Multiple Airlines
Tue 7/2811:30 pm
BFS
-
SEA
3 stops42h 10m
Multiple Airlines
Deal found 5/10$949
This Mytrip deal was found by Cheapflights users on 5/8. 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 9/87:00 am
SEA
-
BFS
3 stops28h 40m
Multiple Airlines
Tue 9/156:40 am
BFS
-
SEA
2 stops22h 00m
Multiple Airlines
Deal found 5/8$973
This Mytrip deal was found by Cheapflights users on 5/8. 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 8/177:00 pm
SEA
-
BFS
2 stops19h 25m
Multiple Airlines
Tue 8/258:20 am
BFS
-
SEA
2 stops35h 25m
Multiple Airlines
Deal found 5/8$1,003
This Mytrip deal was found by Cheapflights users on 5/10. 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 6/95:45 am
SEA
-
BFS
3 stops30h 05m
Multiple Airlines
Tue 6/165:55 am
BFS
-
SEA
3 stops44h 50m
Multiple Airlines
Deal found 5/10$1,030

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 May 12, 2026.

Round-trip from

$891
(Cheapflightsfares)

One-way from

$321
(Kiwi.com)
From Seattle/Tacoma Intl to Belfast
Search Deals
One-way flight from Seattle/Tacoma Intl to Belfast
Search Deals

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 May 12, 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 - BHD

SEABHD

Seattle/Tacoma Intl

Mon 10/5

8:20 pm-7:25 pm

1 stop15h 05m

Belfast City

Thu 10/22

9:35 am-6:25 pm

1 stop16h 50m

$892

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sun 9/27

1:30 pm-10:30 am

1 stop13h 00m

Belfast City

Thu 10/1

4:35 pm-11:35 am

1 stop27h 00m

$910

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Mon 10/19

8:20 pm-6:45 pm

1 stop14h 25m

Belfast City

Wed 10/21

7:40 pm-11:35 am

1 stop23h 55m

$910

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Mon 10/5

3:10 pm-3:30 pm

2 stops16h 20m

Belfast City

Thu 10/22

6:30 am-11:35 am

1 stop13h 05m

$914

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 5/28

3:40 pm-9:40 pm

3 stops22h 00m

Belfast Intl

Mon 6/1

6:30 am-6:45 pm

3 stops44h 15m

$935

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Tue 9/8

9:50 am-4:55 pm

2 stops23h 05m

Belfast City

Tue 9/15

9:50 am-8:29 pm

2 stops18h 39m

$944

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 10/8

9:50 am-4:55 pm

2 stops23h 05m

Belfast City

Thu 10/22

9:50 am-10:04 pm

2 stops20h 14m

$994

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 8/17

7:00 pm-10:25 pm

2 stops19h 25m

Belfast Intl

Tue 8/25

8:20 am-11:45 am

2 stops35h 25m

$1,003

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 6/9

5:45 am-7:50 pm

3 stops30h 05m

Belfast Intl

Tue 6/16

5:55 am-6:45 pm

3 stops44h 50m

$1,030

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sun 6/7

5:45 am-6:25 pm

3 stops28h 40m

Belfast Intl

Sat 6/13

6:55 am-10:40 pm

3 stops23h 45m

$1,042

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/8

Showing 1-10 of 23 resultsSorted by cheapest first
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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
No data available for this route at this time. Please check back soon.

Reviews of airlines servicing Belfast

Get insights into the airlines that provide service to Belfast. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Belfast. Reviews last updated May 12, 2026.
Read reviews from past customers who have flown British Airways from Seattle to Belfast. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
British Airways
6.7
Okay
7,972 reviews

Boarding

6.9

Crew

7.7

Entertainment

6.4

Food

6.4

Overall

6.7

Comfort

6.8

Reviews

1 / 20
10.0
Excellent

Viorica,Mar 2026

PHX - LHR

The food lately is just from poor to very poor. I bealeave that you can serve less quantities for more quality food. Exemple : at breakfast : omlete and vegetarian omlete ....I beleave with less work less personel could be provide some hummus and carrots and some boiled egss plus whatever snacks or drinks you wish....... Thank you in advance
British Airways
6.7
Okay
7,972 reviews
British Airways
6.7
Okay
7,972 reviews

Boarding

6.9

Crew

7.7

Entertainment

6.4

Food

6.4

Overall

6.7

Comfort

6.8

Reviews

1 / 20
10.0
Excellent

Viorica,Mar 2026

PHX - LHR

The food lately is just from poor to very poor. I bealeave that you can serve less quantities for more quality food. Exemple : at breakfast : omlete and vegetarian omlete ....I beleave with less work less personel could be provide some hummus and carrots and some boiled egss plus whatever snacks or drinks you wish....... Thank you in advance

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 1 airline.

  • How long is the flight from Seattle to Belfast?

    Airlines like British Airways fly from Seattle to Belfast in about 16h 15m. 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.

  • What is the cheapest airline to fly from Seattle to Belfast round-trip?

    Flying on British Airways is currently your cheapest option to Belfast, with prices starting at $776.

  • 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

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Seattle to Belfast

See prices for flight routes from nearby airports that may be better suited for you.
Seattle to Belfast Intl flights

Top airline flying from Seattle to Belfast

Discover the top airline that operate flights from Seattle to Belfast. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 12, 2026.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$776Average$1,056FlexibilityNo cancel feeOn-time70%

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