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$725+ 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 9/15. Fares are subject to change and may not be available on all flights or dates of travel.
BHD — SEA
Aug 5 — Aug 121
Tue 8/5
Tue 8/12
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 July 31, 2025.

Round-trip from

$725
(Netflights)

Popular in

November

Cheapest in

May
From Belfast to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($172 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($32 potential savings vs. average RT price).
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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 July 31, 2025.

This Netflights deal was found by Cheapflights users on 7/31. 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 Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/156:40 amBHD - SEA
1 stop12h 55mBritish Airways
Wed 9/241:30 pmSEA - BHD
1 stop14h 25mBritish Airways
Deal found 7/31$725
This oojo deal was found by Cheapflights users on 7/31. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/157:30 pmBHD - SEA
2 stops32h 39mMultiple Airlines
Wed 9/241:02 pmSEA - BHD
2 stops16h 28mMultiple Airlines
Deal found 7/31$768
This KLM deal was found by Cheapflights users on 7/31. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/145:25 pmBHD - SEA
1 stop26h 25mKLM
Thu 10/235:40 pmSEA - BHD
1 stop15h 15mKLM
Deal found 7/31$796
This Trip.com deal was found by Cheapflights users on 7/30. 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 9/46:35 amBFS - SEA
2 stops22h 05mMultiple Airlines
Wed 9/107:00 pmSEA - BFS
2 stops20h 10mMultiple Airlines
Deal found 7/30$803
This American Airlines deal was found by Cheapflights users on 7/30. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/412:40 pmBHD - SEA
1 stop13h 40mAmerican Airlines
Wed 9/103:00 pmSEA - BHD
2 stops16h 35mAmerican Airlines
Deal found 7/30$807
This Delta deal was found by Cheapflights users on 7/31. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/146:30 amBHD - SEA
2 stops17h 40mDelta
Thu 10/231:35 pmSEA - BHD
2 stops19h 20mDelta
Deal found 7/31$809
This oojo deal was found by Cheapflights users on 7/31. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/47:30 pmBHD - SEA
2 stops30h 20mAer Lingus
Thu 8/77:35 pmSEA - BHD
2 stops30h 05mAer Lingus
Deal found 7/31$1,559

Cheapflights Fare Finder

 
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 July 31, 2025.
Use the filters below to find and compare flights from Belfast to Seattle that are best for you.

Fly from

Belfast

Fly to

Seattle

Route

Depart

Return

Price

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 9/15

6:40 am-11:35 am

1 stop12h 55m

Seattle/Tacoma Intl

Wed 9/24

1:30 pm-11:55 am

1 stop14h 25m

$725

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 9/15

7:30 pm-8:09 pm

2 stops32h 39m

Seattle/Tacoma Intl

Wed 9/24

1:02 pm-1:30 pm

2 stops16h 28m

$768

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Tue 10/14

5:25 pm-11:50 am

1 stop26h 25m

Seattle/Tacoma Intl

Thu 10/23

5:40 pm-4:55 pm

1 stop15h 15m

$796

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 9/4

6:35 am-8:40 pm

2 stops22h 05m

Seattle/Tacoma Intl

Wed 9/10

7:00 pm-11:10 pm

2 stops20h 10m

$803

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 9/4

12:40 pm-6:20 pm

1 stop13h 40m

Seattle/Tacoma Intl

Wed 9/10

3:00 pm-3:35 pm

2 stops16h 35m

$807

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Tue 10/14

6:30 am-4:10 pm

2 stops17h 40m

Seattle/Tacoma Intl

Thu 10/23

1:35 pm-4:55 pm

2 stops19h 20m

$809

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/31

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.

Cheapflights Insights

Everything you need to know about your flight from Belfast to Seattle
No data available for this route at this time. Please check back soon.

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 July 31, 2025.
Read reviews from past customers who have flown Delta, KLM, and American Airlines from Belfast to Seattle. 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.
Delta
8.0
Very good
7,981 reviews

Food

7.3

Entertainment

7.9

Boarding

8.2

Overall

8.0

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Delta
8.0
Very good
7,981 reviews
Delta
8.0
Very good
7,981 reviews

Food

7.3

Entertainment

7.9

Boarding

8.2

Overall

8.0

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
KLM
7.8
Good
1,383 reviews
Delta
8.0
Very good
7,981 reviews

Food

7.3

Entertainment

7.9

Boarding

8.2

Overall

8.0

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,981 reviews

Food

7.3

Entertainment

7.9

Boarding

8.2

Overall

8.0

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
British Airways
6.6
Okay
7,222 reviews
Delta
8.0
Very good
7,981 reviews

Food

7.3

Entertainment

7.9

Boarding

8.2

Overall

8.0

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.

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 $725. Additional round-trip tickets that might be worth considering are offered by KLM and American Airlines, with the lowest prices starting at $796 and $807, respectively. Users have found that British Airways is 9% 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 June is currently the most expensive (average of $389). 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 Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Ocean Shores
Lakewood
Lynnwood
Lacey
Leavenworth
Renton
Olympia
Puyallup
Kent
Cle Elum
Chehalis
Kirkland
Issaquah
Aberdeen
Shoreline
Federal Way
Shelton

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Alternative routes for Belfast to Seattle

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