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Cheap flights from Washington to Belfast Intl Airport from £233

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 15/1. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BFS
11 Jan — 18 Jan1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Washington to Belfast Intl

Enter your travel dates to find the best prices.

Best flights from Washington to Belfast Intl
Discover carefully curated flight deals from Washington to Belfast Intl that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 12 December 2025.

Sun 25/114:35SEA - BFS
2 stops20h 20mMultiple Airlines
Sun 1/207:10BFS - SEA
2 stops17h 50mMultiple Airlines
Deal found 11/12£535
Sat 24/114:35SEA - BFS
2 stops19h 05mMultiple Airlines
Sat 31/108:10BFS - SEA
2 stops16h 50mMultiple Airlines
Deal found 10/12£561
Thu 19/214:35SEA - BFS
2 stops24h 00mMultiple Airlines
Thu 26/220:05BFS - SEA
2 stops25h 15mMultiple Airlines
Deal found 11/12£754

Find flight deals from Washington to Belfast Intl

Keep the following information in mind while searching for Washington to Belfast Intl flight deals. Data was last updated 12 December 2025.

Round-trip from

£535

One-way from

£233

Popular in

December

Cheapest in

April

Average price

£1,182
25/1-1/2
  • 25/1-1/2
  • 4 total stops
  • 38h 10m total
  • Washington to Belfast
Search Deals
15/1
  • 15/1
  • 2 total stops
  • 24h 00m total
  • Washington to Belfast
Search Deals
Highest demand for flights based on searches. 11% potential increase in price (£71 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (£34 potential savings vs. average return price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Washington to Belfast Intl 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 12 December 2025.
Use the filters below to find and compare flights from Washington to Belfast Intl Airport that are best for you.

Fly from

Washington

Fly to

Belfast Intl

Route

Depart

Return

Price

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sun 25/1

14:35-18:55

2 stops20h 20m

Belfast Intl

Sun 1/2

07:10-17:00

2 stops17h 50m

£535

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sat 24/1

14:35-17:40

2 stops19h 05m

Belfast Intl

Sat 31/1

08:10-17:00

2 stops16h 50m

£561

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 19/2

14:35-22:35

2 stops24h 00m

Belfast Intl

Thu 26/2

20:05-13:20

2 stops25h 15m

£754

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 15/1

14:35-22:35

2 stops24h 00m

£233

PortlandBelfast

PDX - BFS

PDXBFS

Portland

Fri 15/5

07:23-21:50

3 stops30h 27m

£414

Flights are sorted by cheapest return flights first.

Deals found on 11/12

Best time to book a flight from Washington to Belfast Intl

Have a flexible travel schedule? Discover the best time to fly to Belfast Intl from Washington 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 Washington to Belfast Intl Airport
No data available for this route at this time. Please check back soon.

Related info for your journey

Find useful and relevant information for your journey from Washington to Belfast Intl. 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 Washington to Belfast Intl that include hotel bookings?

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

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

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

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

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

Travelling to a place near Belfast Intl Airport?

Book flights to Belfast Intl Airport if you plan to visit one of these locations
Armagh
Newry
Ballymena
Cookstown
Dungannon

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Alternative routes for Washington to Belfast Intl

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Fly with Cheapflights

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How does Cheapflights help users find flights from Washington to Belfast Intl?

Deals for Washington to Belfast Intl flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

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

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

Users can book flights with no change fees policies with our dedicated filters. Book flights from Washington to Belfast Intl flexibly with Cheapflights today.

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

Yes, Cheapflights offers price alerts on Washington to Belfast Intl 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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