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$357+ 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 5/4. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BHD
Apr 2 — Apr 91
Wed 4/2
Wed 4/9
1 adult, Economy
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Cheap 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 March 28, 2025.

Round-trip from

$789
(British Airways)

One-way from

$357
(Kiwi.com)

Popular in

June

Cheapest in

October

Average price

$764
From Seattle/Tacoma Intl to Belfast
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One-way flight from Seattle/Tacoma Intl to Belfast
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Highest demand for flights based on searches. 17% potential increase in price ($200 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($52 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Find 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 March 28, 2025.

This oojo 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/287:50 pmSEA - BHD
1 stop12h 05mBritish Airways
Tue 11/48:40 amBHD - SEA
1 stop16h 15mBritish Airways
Deal found 3/27$750
This Finnair deal was found by Cheapflights users on 3/28. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/282:35 pmSEA - BHD
1 stop16h 00mMultiple Airlines
Tue 11/46:35 amBHD - SEA
1 stop12h 45mMultiple Airlines
Deal found 3/28$751
This American Airlines deal was found by Cheapflights users on 3/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/283:13 pmSEA - BHD
2 stops16h 42mAmerican Airlines
Tue 11/46:35 amBHD - SEA
1 stop18h 20mAmerican Airlines
Deal found 3/28$764
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/46:07 pmSEA - BHD
1 stop14h 48mDelta
Mon 5/125:25 pmBHD - SEA
1 stop30h 32mDelta
Deal found 3/27$794
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.
Sun 5/113:45 pmSEA - BFS
3 stops21h 45mMultiple Airlines
Sun 5/1810:55 pmBFS - SEA
2 stops29h 33mMultiple Airlines
Deal found 3/27$830
This KLM 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/21:55 pmSEA - BHD
1 stop23h 20mKLM
Mon 5/125:25 pmBHD - SEA
1 stop30h 32mKLM
Deal found 3/27$844
This FlightHub 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/26:45 pmSEA - BHD
2 stops15h 30mAer Lingus
Mon 5/126:00 pmBHD - SEA
2 stops30h 59mAer Lingus
Deal found 3/27$928
This AranGrant deal was found by Cheapflights users on 3/28. 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 AranGrant is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/208:20 pmSEA - BHD
1 stop16h 25mIberia
Sun 7/136:50 amBHD - SEA
1 stop19h 30mIberia
Deal found 3/28$5,309

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 March 28, 2025.
Use the filters below to find and compare flights from Seattle to Belfast that are best for you.

Fly from

Seattle

Fly to

Belfast

Route

Depart

Return

Price

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 4/30

8:20 pm-6:40 pm

1 stop14h 20m

Belfast City

Mon 5/12

6:30 pm-11:10 am

1 stop24h 40m

$789

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sun 5/4

6:07 pm-4:55 pm

1 stop14h 48m

Belfast City

Mon 5/12

5:25 pm-3:57 pm

1 stop30h 32m

$794

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sun 5/11

3:45 pm-9:30 pm

3 stops21h 45m

Belfast Intl

Sun 5/18

10:55 pm-8:28 pm

2 stops29h 33m

$830

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Fri 5/2

1:55 pm-9:15 pm

1 stop23h 20m

Belfast City

Mon 5/12

5:25 pm-3:57 pm

1 stop30h 32m

$844

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Fri 5/2

1:35 pm-3:30 pm

2 stops17h 55m

Belfast City

Sun 5/11

6:50 am-11:30 am

1 stop12h 40m

$864

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 5/3

6:07 pm-4:55 pm

1 stop14h 48m

Belfast City

Sat 5/10

6:30 am-4:08 pm

2 stops17h 38m

$915

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Fri 5/2

6:45 pm-6:15 pm

2 stops15h 30m

Belfast City

Mon 5/12

6:00 pm-4:59 pm

2 stops30h 59m

$928

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Fri 6/20

8:20 pm-8:45 pm

1 stop16h 25m

Belfast City

Sun 7/13

6:50 am-6:20 pm

1 stop19h 30m

$5,309

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sun 5/4

7:00 pm-10:25 am

2 stops55h 25m

$357

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sun 5/4

7:00 pm-12:05 pm

2 stops33h 05m

$385

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/27

Showing 1-10 of 12 results
1
2

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

What is the cheapest time of day to fly from SEA to BFS?

Find hourly flight availability from Seattle to Belfast. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 28, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Belfast in the morning. If you’re flexible enough to do this you can expect to save up to 23% on your trip compared to booking a flight at noon.

Rainfall in Belfast by month

Plan your trip to Belfast by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Belfast ranges from 2.0 - 3.5 inches per month. October is typically the wettest month, when rainfall can reach 3.5 in. April is typically the driest time to visit Belfast when rainfall is around 2.0 in.

Temperature in Belfast by month

Plan your trip to Belfast by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Belfast, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 60.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 41.0 F).

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 March 28, 2025.
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Comfort

8.0

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very good
7,896 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Comfort

8.0

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,321 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Comfort

8.0

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Comfort

8.0

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Aer Lingus
7.0
Good
1,062 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Comfort

8.0

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Iberia
7.0
Good
2,651 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Comfort

8.0

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

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.

  • What are the cheapest airlines flying from Seattle to Belfast round-trip?

    Flying on British Airways is currently your cheapest option to Belfast, with prices starting at $789. Additional round-trip tickets that might be worth considering are offered by Delta and KLM, with the lowest prices starting at $794 and $844, respectively. British Airways is 16% cheaper than the average price of flights available within the next 90 days to this destination.

  • 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.

  • What is the cheapest month to book a flight from Seattle to Belfast?

    Currently, February is the cheapest month in which you can book a flight from Seattle to Belfast (average of $657). Flying from Seattle to Belfast in June is currently the most expensive (average of $1,189). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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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
Seattle to Belfast City flights
Portland to Belfast Intl flights
Portland to Belfast City 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 March 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$544Average$866FlexibilityNo cancel feeOn-time70%
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