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Cheap flights from Belfast to Seattle from £552

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/3. Fares are subject to change and may not be available on all flights or dates of travel.
BHD — SEA
17 Oct — 24 Oct1
1 adult
1 adult, Economy

Cheap 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 17 September 2025.

Round-trip from

£552

Popular in

November

Cheapest in

May

Average price

£551
American Airlines
  • American Airlines
  • 5/3-9/3
  • 3 total stops
  • 35h 47m total
  • Belfast to Seattle
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (£66 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£17 potential savings vs. average return price).
Search Deals
Average for round-trip flights in September 2025
Search Deals

Find flight deals from Belfast to Seattle

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 17 September 2025.

Mon 6/1007:05BHD - SEA
3 stops37h 54mMultiple Airlines
Wed 8/1008:40SEA - BHD
2 stops20h 00mMultiple Airlines
Deal found 15/9£785
Mon 15/906:55BHD - SEA
2 stops18h 55mAer Lingus
Wed 24/919:35SEA - BHD
2 stops14h 05mAer Lingus
Deal found 13/9£845
Mon 15/906:40BHD - SEA
1 stop12h 55mBritish Airways
Wed 24/913:30SEA - BHD
1 stop16h 00mBritish Airways
Deal found 13/9£882

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 17 September 2025.
Use the filters below to find and compare flights from Belfast to Seattle that are best for you.

Fly from

Belfast

Fly to

Seattle

Route

Depart

Return

Price

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/3

06:35-16:55

1 stop18h 20m

Seattle/Tacoma Intl

Mon 9/3

13:48-14:15

2 stops17h 27m

£552

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/3

17:45-16:55

1 stop31h 10m

Seattle/Tacoma Intl

Mon 9/3

19:50-18:35

1 stop15h 45m

£554

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Mon 6/10

07:05-12:59

3 stops37h 54m

Seattle/Tacoma Intl

Wed 8/10

08:40-12:40

2 stops20h 00m

£785

Flights are sorted by cheapest return flights first.

Deals found on 13/9

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 17 September 2025.
Read through reviews of airlines operating flights from Belfast to Seattle, such as American Airlines and British Airways. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
American Airlines
7.2
Good
10,000 reviews
Check prices

Overall

7.2

Crew

8.0

Boarding

7.5

Comfort

7.2

Food

6.4

Entertainment

6.9

Reviews

1 / 20
2.0
Mediocre

Nordia,Sept 2025

KIN - MIA

We were to land in Miami sometime after 3pm but couldn’t due to bad weather, we flew around for 2 hrs until we had to land in Forth Myers to refuel, we had to sit another 2 hrs at Forth Myers until given the clearance to refuel, we were hungry, thirsty and frustrated at that point. All the had on the flight to offer was a small plastic glass of water and a pack of biscoff, I requested a cup of tea and was told none was there. We were basically at another airport and not one of the staff could consider that the passengers might be hungry or thirsty being on a plane for around 8 hrs, which you weren’t prepared for, at least find some hot water on board.
American Airlines
7.2
Good
10,000 reviews
American Airlines
7.2
Good
10,000 reviews
Check prices

Overall

7.2

Crew

8.0

Boarding

7.5

Comfort

7.2

Food

6.4

Entertainment

6.9

Reviews

1 / 20
2.0
Mediocre

Nordia,Sept 2025

KIN - MIA

We were to land in Miami sometime after 3pm but couldn’t due to bad weather, we flew around for 2 hrs until we had to land in Forth Myers to refuel, we had to sit another 2 hrs at Forth Myers until given the clearance to refuel, we were hungry, thirsty and frustrated at that point. All the had on the flight to offer was a small plastic glass of water and a pack of biscoff, I requested a cup of tea and was told none was there. We were basically at another airport and not one of the staff could consider that the passengers might be hungry or thirsty being on a plane for around 8 hrs, which you weren’t prepared for, at least find some hot water on board.
British Airways
6.7
Okay
7,363 reviews
American Airlines
7.2
Good
10,000 reviews
Check prices

Overall

7.2

Crew

8.0

Boarding

7.5

Comfort

7.2

Food

6.4

Entertainment

6.9

Reviews

1 / 20
2.0
Mediocre

Nordia,Sept 2025

KIN - MIA

We were to land in Miami sometime after 3pm but couldn’t due to bad weather, we flew around for 2 hrs until we had to land in Forth Myers to refuel, we had to sit another 2 hrs at Forth Myers until given the clearance to refuel, we were hungry, thirsty and frustrated at that point. All the had on the flight to offer was a small plastic glass of water and a pack of biscoff, I requested a cup of tea and was told none was there. We were basically at another airport and not one of the staff could consider that the passengers might be hungry or thirsty being on a plane for around 8 hrs, which you weren’t prepared for, at least find some hot water on board.

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 2 airlines. 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 £552, American Airlines can have you in Seattle from Belfast in 18h 20m. Airlines will cover a distance of 4472 mi.

  • What are the cheapest airlines flying from Belfast to Seattle round-trip?

    British Airways, at £431, was found to be the cheapest airline from Belfast to Seattle. An alternate airline flying to your destination would be American Airlines. British Airways is priced at 28% lower than the current average price of a flight leaving 3 months from now.

  • 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.

  • What is the cheapest month to book a flight from Belfast to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Belfast to Seattle (average of £622). Flying from Belfast to Seattle in July is currently the most expensive (average of £946). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Tacoma
Leavenworth
Bothell
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 City to Seattle flights

Top 2 airlines flying from Belfast to Seattle

Discover the top 2 airlines 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 17 September 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest£431Average£515FlexibilityNo cancel feeOn-time70%
Search British Airways flights
American AirlinesCheapest£551Average£551FlexibilityNo 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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