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Cheap flights from Belfast Intl Airport to Seattle from £348

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 1/10. Fares are subject to change and may not be available on all flights or dates of travel.
BFS — SEA
15 May — 22 May1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Belfast Intl to Seattle

Enter your travel dates to find the best prices.

Cheapest flights from Belfast Intl to Seattle
Explore the most affordable flight options available from Belfast Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 15 April 2026.

Tue 26/523:30
BFS
-
SEA
3 stops42h 10m
Multiple Airlines
Tue 2/615:40
SEA
-
BFS
3 stops23h 40m
Multiple Airlines
Deal found 10/4£691
Mon 14/908:15
BFS
-
SEA
2 stops20h 25m
Multiple Airlines
Sun 20/915:40
SEA
-
BFS
2 stops20h 35m
Multiple Airlines
Deal found 13/4£701

Find flight deals from Belfast Intl to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Belfast Intl (BFS) 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 15 April 2026.

Round-trip from

£691

One-way from

£348
26/5-2/6
  • 26/5-2/6
  • 6 total stops
  • 65h 50m total
  • Belfast to Seattle
Search Deals
1/10
  • 1/10
  • 3 total stops
  • 35h 22m total
  • Belfast to Seattle
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Belfast Intl 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 15 April 2026.
Use the filters below to find and compare flights from Belfast Intl Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight
Fastest return journey

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 14/9

08:15-20:40

2 stops20h 25m

Seattle/Tacoma Intl

Sun 20/9

15:40-20:15

2 stops20h 35m

£701

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Tue 26/5

08:20-20:40

2 stops20h 20m

Seattle/Tacoma Intl

Tue 2/6

15:40-20:55

2 stops21h 15m

£744
Cheapest one-way

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 1/10

07:00-10:22

3 stops35h 22m

£348
Fastest single journey

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Tue 8/9

07:00-20:40

2 stops21h 40m

£405

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Mon 7/9

06:40-20:40

2 stops22h 00m

£466

Flights are sorted by cheapest return flights first.

Deals found on 13/4

Sorted by cheapest first

Best time to book a flight from Belfast Intl to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle 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.

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 15 April 2026.
Read reviews from past customers who have flown with American Airlines from Belfast Intl Airport 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.
American Airlines
7.1
Good
11,581 reviews
Check prices

Comfort

7.2

Overall

7.1

Entertainment

6.9

Food

6.4

Boarding

7.5

Crew

7.9

Reviews

1 / 20
4.0
Okay

Elizabeth,Mar 2026

ORD - MIA

Staff was rude and flight attendants 2 out of 3 looked like they had just been thru a hurricane.
American Airlines
7.1
Good
11,581 reviews
American Airlines
7.1
Good
11,581 reviews
Check prices

Comfort

7.2

Overall

7.1

Entertainment

6.9

Food

6.4

Boarding

7.5

Crew

7.9

Reviews

1 / 20
4.0
Okay

Elizabeth,Mar 2026

ORD - MIA

Staff was rude and flight attendants 2 out of 3 looked like they had just been thru a hurricane.

Related info for your journey

Find useful and relevant information for your journey from Belfast Intl 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 Intl?

    Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Belfast Intl to Seattle. 1 airline have flights to Seattle/Tacoma Intl from Belfast Intl on a regular basis. Booking flights from Belfast Intl to Seattle/Tacoma Intl should not be difficult; the airport handles an average of 0 inbound flights from Belfast Intl per day.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Belfast Intl 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 Intl to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
Belfast City to Seattle flights

Top airline flying from Belfast Intl to Seattle

Discover the top airline that operate flights from Belfast Intl 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 15 April 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest£554Average£554FlexibilityNo 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 Intl to Seattle?

Cheapflights makes it easy to find Belfast Intl to Seattle flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

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

By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to Seattle from Belfast Intl.

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

Yes, we can. To see specific flights from Belfast Intl to Seattle with no change fees, users can toggle flexible booking options after using the search form above to find flights.

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

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Seattle from Belfast Intl today and book when prices fit your budget.

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