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Cheap flights from Belfast Intl Airport to Washington from £381

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 23/10. Fares are subject to change and may not be available on all flights or dates of travel.
BFS — SEA
26 Aug — 2 Sep1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Belfast Intl to Washington

Enter your travel dates to find the best prices.

Cheapest flights from Belfast Intl to Washington
Explore the most affordable flight options available from Belfast Intl to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 27 July 2026.

Tue 8/908:20
BFS
-
SEA
2 stops20h 20m
Multiple Airlines
Sun 13/915:40
SEA
-
BFS
2 stops22h 55m
Multiple Airlines
Deal found 24/7£599
Mon 7/910:00
BFS
-
SEA
2 stops33h 45m
Multiple Airlines
Sun 13/915:40
SEA
-
BFS
2 stops23h 30m
Multiple Airlines
Deal found 24/7£609
Mon 31/806:40
BFS
-
SEA
1 stop21h 23m
Multiple Airlines
Sun 6/907:38
SEA
-
BFS
2 stops31h 32m
Multiple Airlines
Deal found 25/7£656
Mon 7/908:15
BFS
-
SEA
2 stops35h 30m
Multiple Airlines
Mon 14/919:00
SEA
-
BFS
2 stops17h 25m
Multiple Airlines
Deal found 24/7£684

Find flight deals from Belfast Intl to Washington

Keep the following information in mind while searching for Belfast Intl to Washington flight deals. Data was last updated 27 July 2026.

Round-trip from

£599

One-way from

£381
8/9-13/9
  • 8/9-13/9
  • 4 total stops
  • 43h 15m total
  • Belfast to Washington
Search Deals
23/10
  • 23/10
  • 2 total stops
  • 37h 40m total
  • Belfast to Washington
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Belfast Intl to Washington 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 27 July 2026.
Use the filters below to find and compare flights from Belfast Intl Airport to Washington that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 31/8

06:40-20:03

1 stop21h 23m

Seattle/Tacoma Intl

Sun 6/9

07:38-23:10

2 stops31h 32m

£656

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 7/9

08:15-11:45

2 stops35h 30m

Seattle/Tacoma Intl

Mon 14/9

19:00-20:25

2 stops17h 25m

£684

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Tue 8/9

14:45-18:45

2 stops36h 00m

Seattle/Tacoma Intl

Sun 13/9

21:40-20:15

1 stop14h 35m

£718
Fastest return journey

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 7/9

18:50-11:55

2 stops25h 05m

Seattle/Tacoma Intl

Sun 13/9

21:40-21:55

1 stop16h 15m

£725

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Tue 18/8

05:55-10:05

3 stops36h 10m

Seattle/Tacoma Intl

Fri 28/8

15:40-21:50

2 stops22h 10m

£766

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 3/9

06:10-20:40

2 stops22h 30m

Seattle/Tacoma Intl

Thu 10/9

15:40-19:20

2 stops19h 40m

£832
Cheapest one-way
Fastest single journey

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Fri 23/10

06:15-19:00

1 stop20h 45m

£442

Flights are sorted by cheapest return flights first.

Deals found on 26/7

Sorted by cheapest first

Best time to book a flight from Belfast Intl to Washington

Have a flexible travel schedule? Discover the best time to fly to Washington from Belfast Intl 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 Intl Airport to Washington

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Related info for your journey

Find useful and relevant information for your journey from Belfast Intl to Washington. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    Yes. In addition to deals on Belfast Intl to Washington flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Belfast Intl to Washington?

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

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

    Yes. Cheapflights offers flight deals from Belfast Intl to Washington by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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

Need flexible booking options for your flight to Washington from Belfast Intl? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

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