Find flights
When to book

Cheap flights from Washington to Belfast Intl Airport from £557

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 20/4. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BFS
30 Mar — 6 Apr1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Washington to Belfast Intl

Enter your travel dates to find the best prices.

Cheapest flights from Washington to Belfast Intl
Explore the most affordable flight options available from Washington to Belfast Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 28 February 2026.

Mon 20/415:40
SEA
-
BFS
3 stops23h 40m
Multiple Airlines
Wed 29/406:10
BFS
-
SEA
2 stops22h 30m
Multiple Airlines
Deal found 27/2£557
Tue 14/415:40
SEA
-
BFS
2 stops21h 15m
Multiple Airlines
Tue 21/406:15
BFS
-
SEA
2 stops22h 25m
Multiple Airlines
Deal found 28/2£577
Thu 3/919:00
SEA
-
BFS
2 stops17h 35m
Multiple Airlines
Fri 11/908:30
BFS
-
SEA
2 stops20h 10m
Multiple Airlines
Deal found 28/2£621
Sun 12/419:00
SEA
-
BFS
2 stops18h 00m
Multiple Airlines
Sun 19/420:20
BFS
-
SEA
3 stops32h 20m
Multiple Airlines
Deal found 26/2£633
Wed 20/515:40
SEA
-
BFS
3 stops24h 25m
Multiple Airlines
Mon 25/509:30
BFS
-
SEA
3 stops38h 30m
Multiple Airlines
Deal found 26/2£690
Tue 18/819:00
SEA
-
BFS
2 stops19h 15m
Multiple Airlines
Sat 29/809:40
BFS
-
SEA
2 stops34h 05m
Multiple Airlines
Deal found 28/2£727
Thu 14/515:35
PDX
-
BFS
2 stops23h 15m
Multiple Airlines
Sun 24/518:00
BFS
-
PDX
2 stops27h 10m
Multiple Airlines
Deal found 26/2£732
Sat 11/415:30
PDX
-
BFS
3 stops23h 10m
Multiple Airlines
Sat 18/406:00
BFS
-
PDX
3 stops44h 00m
Multiple Airlines
Deal found 25/2£882
Wed 20/519:05
PDX
-
BFS
3 stops20h 05m
Multiple Airlines
Mon 25/506:30
BFS
-
PDX
3 stops20h 35m
Multiple Airlines
Deal found 26/2£887

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 28 February 2026.

Round-trip from

£557

One-way from

£245
20/4-29/4
  • 20/4-29/4
  • 5 total stops
  • 46h 10m total
  • Washington to Belfast
Search Deals
11/4
  • 11/4
  • 3 total stops
  • 56h 10m total
  • Washington to Belfast
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 28 February 2026.
Use the filters below to find and compare flights from Washington to Belfast Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 20/4

15:40-15:35

2 stops15h 55m

Belfast Intl

Wed 29/4

06:10-20:40

2 stops22h 30m

£591

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sun 12/4

19:00-21:00

2 stops18h 00m

Belfast Intl

Sun 19/4

20:20-20:40

3 stops32h 20m

£633

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Wed 20/5

15:40-00:05

3 stops24h 25m

Belfast Intl

Mon 25/5

09:30-16:00

3 stops38h 30m

£690

PortlandBelfast

PDX - BFS

PDXBFS

Portland

Thu 14/5

15:35-22:50

2 stops23h 15m

Belfast Intl

Sun 24/5

18:00-13:10

2 stops27h 10m

£732

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 18/8

15:40-22:15

2 stops22h 35m

Belfast Intl

Sat 29/8

07:40-17:55

3 stops42h 15m

£740

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 21/8

19:00-21:50

2 stops18h 50m

Belfast Intl

Fri 28/8

06:05-20:40

2 stops22h 35m

£783

PortlandBelfast

PDX - BFS

PDXBFS

Portland

Sat 11/4

15:30-22:40

3 stops23h 10m

Belfast Intl

Sat 18/4

06:00-18:00

3 stops44h 00m

£882

PortlandBelfast

PDX - BFS

PDXBFS

Portland

Wed 20/5

19:05-23:10

3 stops20h 05m

Belfast Intl

Mon 25/5

06:30-19:05

3 stops20h 35m

£887

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 30/6

05:40-15:15

3 stops25h 35m

Belfast Intl

Tue 7/7

23:30-21:07

2 stops29h 37m

£904

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 6/8

08:00-19:30

2 stops27h 30m

Belfast Intl

Sat 15/8

09:30-17:10

3 stops39h 40m

£930

Flights are sorted by cheapest return flights first.

Deals found on 27/2

Sorted by cheapest first

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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 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?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Washington to Belfast Intl for you. Better yet — we are completely free to use.

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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.