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Cheap flights from Belfast to Seattle from £346

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 3/5. Fares are subject to change and may not be available on all flights or dates of travel.
BHD — SEA
23 Apr — 30 Apr1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Belfast to Seattle

Enter your travel dates to find the best prices.

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 24 March 2026.

Thu 7/506:10
BFS
-
SEA
2 stops19h 45m
Multiple Airlines
Thu 14/519:00
SEA
-
BFS
2 stops17h 35m
Multiple Airlines
Deal found 23/3£598
Wed 22/410:05
BHD
-
SEA
1 stop16h 20m
British Airways
Sun 26/413:19
SEA
-
BHD
2 stops20h 21m
British Airways
Deal found 19/3£725
Wed 6/511:35
BHD
-
SEA
2 stops21h 01m
British Airways
Sun 10/520:20
SEA
-
BHD
1 stop16h 15m
British Airways
Deal found 22/3£729
Fri 11/909:35
BHD
-
SEA
2 stops39h 54m
British Airways
Mon 14/906:24
SEA
-
BHD
2 stops22h 31m
British Airways
Deal found 20/3£731
Fri 8/506:30
BHD
-
SEA
1 stop13h 05m
British Airways
Tue 12/513:30
SEA
-
BHD
1 stop22h 10m
British Airways
Deal found 23/3£735
Wed 5/808:30
BFS
-
SEA
3 stops40h 45m
Multiple Airlines
Sun 16/819:10
SEA
-
BFS
2 stops18h 20m
Multiple Airlines
Deal found 23/3£903

Find 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 24 March 2026.

Round-trip from

£598

One-way from

£328
7/5-14/5
  • 7/5-14/5
  • 4 total stops
  • 37h 20m total
  • Belfast to Seattle
Search Deals
3/5
  • 3/5
  • 3 total stops
  • 44h 36m total
  • Belfast to Seattle
Search Deals

Cheapflights Fare Finder

 
Customise 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 858,174 searches. Data last updated 24 March 2026.
Use the filters below to find and compare flights from Belfast to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 7/5

06:10-17:55

2 stops19h 45m

Seattle/Tacoma Intl

Thu 14/5

19:00-20:35

2 stops17h 35m

£598

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Fri 11/9

06:30-18:25

1 stop19h 55m

Seattle/Tacoma Intl

Mon 14/9

06:24-12:55

2 stops22h 31m

£725
Fastest return journey

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Wed 22/4

10:05-18:25

1 stop16h 20m

Seattle/Tacoma Intl

Sun 26/4

13:19-17:40

2 stops20h 21m

£725

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Wed 6/5

11:35-00:36

2 stops21h 01m

Seattle/Tacoma Intl

Sun 10/5

20:20-20:35

1 stop16h 15m

£729

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Fri 8/5

19:35-22:38

2 stops35h 03m

Seattle/Tacoma Intl

Tue 12/5

13:30-15:20

1 stop17h 50m

£738

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Wed 5/8

08:30-10:40

3 stops34h 10m

Seattle/Tacoma Intl

Sun 16/8

05:40-18:25

3 stops28h 45m

£972
Cheapest one-way

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Sun 3/5

20:10-10:36

3 stops46h 26m

£346
Fastest single journey

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Sun 3/5

19:10-11:35

1 stop24h 25m

£697

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 3/8

15:20-11:35

1 stop28h 15m

£868

Flights are sorted by cheapest return flights first.

Deals found on 19/3

Sorted by cheapest first

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 return 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 24 March 2026.
Read through reviews of airlines operating flights from Belfast to Seattle, such as American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
American Airlines
7.1
Good
11,491 reviews
Check prices

Crew

7.9

Comfort

7.2

Overall

7.1

Food

6.4

Entertainment

6.9

Boarding

7.5

Reviews

1 / 20
2.0
Mediocre

Anonymous,Mar 2026

MIA - SFO

Horrible. When they power flights for other airlines there is nothing they can do to change or accommodate any changes
American Airlines
7.1
Good
11,491 reviews
American Airlines
7.1
Good
11,491 reviews
Check prices

Crew

7.9

Comfort

7.2

Overall

7.1

Food

6.4

Entertainment

6.9

Boarding

7.5

Reviews

1 / 20
2.0
Mediocre

Anonymous,Mar 2026

MIA - SFO

Horrible. When they power flights for other airlines there is nothing they can do to change or accommodate any changes

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?

    Most people fly into Seattle/Tacoma Intl (SEA) if they book a flight to Seattle from Belfast. On average, Seattle/Tacoma Intl has 0 inbound flights from Belfast per day from 1 airline. Seattle/Tacoma Intl is conveniently located just 11.4 mi from Seattle’s city center.

  • How long is the flight from Belfast to Seattle?

    For as low as £725, British Airways can have you in Seattle from Belfast in 16h 20m. Airlines will cover a distance of 4472 mi.

  • 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 holiday 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.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Tacoma
Federal Way
SeaTac

Browse thousands of different options on Cheapflights for your next trip

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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

Top airline flying from Belfast to Seattle

Discover the top airline that operate flights from Belfast to Seattle. 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 858,174 searches. Data last updated 24 March 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest£562Average£562FlexibilityNo cancel feeOn-time71%
Search American Airlines flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Belfast to Seattle?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Belfast to Seattle. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from Belfast to Seattle?

Millions of users choose and trust Cheapflights to book the best flight deals from Belfast to Seattle for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

Can Cheapflights find flights from Belfast to Seattle with no change fees?

Certainly. Search results for flights to Seattle from Belfast shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Belfast to Seattle become cheaper?

Yes, Cheapflights offers price alerts on Belfast to Seattle flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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