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$503+ Cheap flights from Belfast to Seattle (SEA)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/3. Fares are subject to change and may not be available on all flights or dates of travel.
BHD — SEA
Jan 26 — Feb 21
Sun 1/26
Sun 2/2
1 adult, Economy
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Cheap flight deals from Belfast to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Belfast (BF1) to Seattle (SEA). 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 January 21, 2025.

Round-trip from

$503
(Trip.com)

Popular in

July

Cheapest in

February

Average price

$957
From Belfast to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 16% potential increase in price ($170 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($24 potential savings vs. average RT price).
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Average for round-trip flights in January 2025
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Find flight deals from Belfast to Seattle

Cheapest flights from Belfast to Seattle
Explore the most affordable flight options available from Belfast to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 21, 2025.

This Trip.com deal was found by Cheapflights users on 1/21. 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.
Mon 3/36:30 amBFS - SEA
2 stops18h 30mMultiple Airlines
Mon 3/103:35 pmSEA - BFS
2 stops21h 35mMultiple Airlines
Deal found 1/21$503
This Expedia deal was found by Cheapflights users on 1/21. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/146:45 amBHD - SEA
1 stop12h 35mBritish Airways
Sun 3/237:50 pmSEA - BHD
1 stop15h 50mBritish Airways
Deal found 1/21$583
This Delta deal was found by Cheapflights users on 1/21. 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.
Mon 2/36:30 amBHD - SEA
1 stop13h 16mDelta
Mon 2/102:09 pmSEA - BHD
1 stop22h 51mDelta
Deal found 1/21$629
This Trip.com deal was found by Cheapflights users on 1/21. 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.
Fri 3/147:25 amBHD - SEA
2 stops17h 35mMultiple Airlines
Sun 3/233:35 pmSEA - BHD
2 stops21h 55mMultiple Airlines
Deal found 1/21$669
This TravelUp deal was found by Cheapflights users on 1/21. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/146:30 amBHD - SEA
1 stop13h 10mKLM
Sun 3/237:55 pmSEA - BHD
2 stops18h 05mKLM
Deal found 1/21$720
This Finnair deal was found by Cheapflights users on 1/21. 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.
Thu 5/84:20 pmBHD - SEA
2 stops34h 29mFinnair
Thu 7/171:30 pmSEA - BHD
1 stop13h 40mFinnair
Deal found 1/21$728
This American Airlines deal was found by Cheapflights users on 1/21. 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.
Thu 5/84:20 pmBHD - SEA
1 stop27h 15mAmerican Airlines
Thu 5/295:40 pmSEA - BHD
2 stops16h 25mAmerican Airlines
Deal found 1/21$730

Find flights from Belfast to Seattle within your budget

Customize your flight search to find flights from Belfast to Seattle 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 January 21, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 3/3

6:30 am-5:00 pm

2 stops18h 30m

Seattle/Tacoma Intl

Mon 3/10

3:35 pm-8:10 pm

2 stops21h 35m

$503

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Fri 3/14

6:45 am-12:20 pm

1 stop12h 35m

Seattle/Tacoma Intl

Sun 3/23

7:50 pm-6:40 pm

1 stop15h 50m

$583

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 2/3

6:30 am-11:46 am

1 stop13h 16m

Seattle/Tacoma Intl

Mon 2/10

2:09 pm-9:00 pm

1 stop22h 51m

$629

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Fri 3/14

7:25 am-6:00 pm

2 stops17h 35m

Seattle/Tacoma Intl

Sun 3/23

3:35 pm-8:30 pm

2 stops21h 55m

$669

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Fri 3/14

6:30 am-12:40 pm

1 stop13h 10m

Seattle/Tacoma Intl

Sun 3/23

7:55 pm-9:00 pm

2 stops18h 05m

$720

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/8

4:20 pm-6:49 pm

2 stops34h 29m

Seattle/Tacoma Intl

Thu 7/17

1:30 pm-11:10 am

1 stop13h 40m

$728

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/8

4:20 pm-11:35 am

1 stop27h 15m

Seattle/Tacoma Intl

Thu 5/29

5:40 pm-6:05 pm

2 stops16h 25m

$730

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 2/17

6:35 am-6:15 pm

2 stops19h 40m

$546

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 2/17

9:10 am-4:55 pm

1 stop15h 45m

$634

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/21

Best time to book a flight from Belfast to Seattle

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

Travel insights for flights from Belfast to Seattle

Get recent, data-driven insights about flights from Belfast to Seattle including ideal travel times, pricing trends, and more.

Rainfall in Seattle by month

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

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

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

If weather is an important factor for your trip to Seattle, 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 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. 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 Seattle. Reviews last updated January 21, 2025.
Delta
8.0
Very good
8,521 reviews

Comfort

8.0

Crew

8.6

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Reviews

1 / 10

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Delta
8.0
Very good
8,521 reviews
Delta
8.0
Very good
8,521 reviews

Comfort

8.0

Crew

8.6

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Reviews

1 / 10

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

KLM
7.8
Good
1,341 reviews
Delta
8.0
Very good
8,521 reviews

Comfort

8.0

Crew

8.6

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Reviews

1 / 10

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Finnair
7.6
Good
1,286 reviews
Delta
8.0
Very good
8,521 reviews

Comfort

8.0

Crew

8.6

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Reviews

1 / 10

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
8,521 reviews

Comfort

8.0

Crew

8.6

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Reviews

1 / 10

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Aer Lingus
7.1
Good
1,082 reviews
Delta
8.0
Very good
8,521 reviews

Comfort

8.0

Crew

8.6

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Reviews

1 / 10

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

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

    Seattle/Tacoma Intl (SEA) is the airport you will fly into if you book a flight from Belfast to Seattle. You should not have trouble finding flights to Seattle/Tacoma Intl from Belfast; the airport handles an average of 0 inbound flights from Belfast per day. You should also have plenty of airline options to choose from since 0 airlines have flights to the Seattle airport from Belfast. It is only a 11.4 mi journey from Seattle/Tacoma Intl (SEA) to Seattle’s city center.

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

    Flying on British Airways is currently your cheapest option to Seattle, with prices starting at $583. Additional round-trip tickets that might be worth considering are offered by Delta and KLM, with the lowest prices starting at $629 and $720, respectively. Users have found that British Airways is 33% cheaper than the other options available to this destination.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Belfast to Seattle 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 Belfast to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Belfast to Seattle (average of $238). Flying from Belfast to Seattle in July is currently the most expensive (average of $411). 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

Traveling to a place near Belfast?

Book flights to Belfast if you plan to visit one of these locations
SeaTac
Tukwila
Renton
Tacoma
Lacey
Federal Way
Ocean Shores
Leavenworth
Olympia
Marysville
Centralia
Cle Elum
Mukilteo
Aberdeen
Lakewood
Issaquah
Shoreline
Lynnwood
Shelton
Silverdale

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Alternative routes for Belfast to Seattle

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