HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Seattle

$792+ Cheap flights from Belfast to Seattle (SEA)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/8. Fares are subject to change and may not be available on all flights or dates of travel.
BHD — SEA
Apr 29 — May 61
Tue 4/29
Tue 5/6
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Belfast to Seattle with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 April 24, 2025.

Round-trip from

$792
(British Airways)

Popular in

July

Cheapest in

May

Average price

$690
From Belfast to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 18% potential increase in price ($196 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($29 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 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 April 24, 2025.

This British Airways deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/812:40 pmBHD - SEA
1 stop13h 40mBritish Airways
Thu 5/221:30 pmSEA - BHD
1 stop13h 40mBritish Airways
Deal found 4/23$792
This KLM deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/86:30 amBHD - SEA
1 stop17h 27mKLM
Thu 5/222:10 pmSEA - BHD
1 stop23h 05mKLM
Deal found 4/23$799
This American Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/86:35 amBHD - SEA
1 stop13h 00mAmerican Airlines
Thu 5/221:30 pmSEA - BHD
1 stop13h 40mAmerican Airlines
Deal found 4/22$816
This Trip.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/216:00 amBFS - SEA
2 stops37h 25mMultiple Airlines
Wed 5/283:45 pmSEA - BFS
2 stops23h 25mMultiple Airlines
Deal found 4/22$817
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/86:30 amBHD - SEA
2 stops19h 20mDelta
Thu 5/2911:40 amSEA - BHD
2 stops21h 15mDelta
Deal found 4/23$865
This American Airlines deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/812:40 pmBHD - SEA
2 stops16h 59mMultiple Airlines
Thu 5/227:35 pmSEA - BHD
2 stops15h 45mMultiple Airlines
Deal found 4/23$1,151

Cheapflights Fare Finder

Customize 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 2,558,603 searches. Data last updated April 24, 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 5/8

12:40 pm-6:20 pm

1 stop13h 40m

Seattle/Tacoma Intl

Thu 5/22

1:30 pm-11:10 am

1 stop13h 40m

$792

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/8

6:30 am-3:57 pm

1 stop17h 27m

Seattle/Tacoma Intl

Thu 5/22

2:10 pm-9:15 pm

1 stop23h 05m

$799

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/8

6:35 am-11:35 am

1 stop13h 00m

Seattle/Tacoma Intl

Thu 5/22

1:30 pm-11:10 am

1 stop13h 40m

$816

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Wed 5/21

6:00 am-11:25 am

2 stops37h 25m

Seattle/Tacoma Intl

Wed 5/28

3:45 pm-11:10 pm

2 stops23h 25m

$817

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/8

6:30 am-5:50 pm

2 stops19h 20m

Seattle/Tacoma Intl

Thu 5/29

11:40 am-4:55 pm

2 stops21h 15m

$865

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/8

12:40 pm-9:39 pm

2 stops16h 59m

Seattle/Tacoma Intl

Thu 5/22

7:35 pm-7:20 pm

2 stops15h 45m

$1,151

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Wed 7/30

6:50 am-5:50 pm

2 stops19h 00m

$1,046

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Wed 7/30

8:15 pm-11:35 am

1 stop23h 20m

$1,200

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/23

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 round-trip 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

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

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 April 24, 2025.
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,920 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
KLM
7.8
Good
1,333 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Aer Lingus
7.0
Good
1,068 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
British Airways
6.6
Okay
6,799 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Food

7.3

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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?

    Seattle/Tacoma Intl (SEA) is the airport you will fly into if you book a flight from Belfast to Seattle. You should not have trouble finding flights to Seattle/Tacoma Intl from Belfast; the airport handles an average of 0 inbound flights from Belfast per day. You should also have plenty of airline options to choose from since 0 airlines have flights to the Seattle airport from Belfast. It is only a 11.4 mi journey from Seattle/Tacoma Intl (SEA) to Seattle’s city center.

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

    Flying on British Airways is currently your cheapest option to Seattle, with prices starting at $792. Additional round-trip tickets that might be worth considering are offered by KLM and American Airlines, with the lowest prices starting at $799 and $816, respectively. Users have found that British Airways is 5% cheaper than the other options available to this destination.

  • 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 vacation 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 $238). Flying from Belfast to Seattle in July is currently the most expensive (average of $411). 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

Traveling to a place near Belfast?

Book flights to Belfast if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Renton
Lakewood
Ocean Shores
Lacey
Leavenworth
Federal Way
Olympia
Shoreline
Cle Elum
Centralia
Kent
Aberdeen
Lynnwood
Shelton
Silverdale
Redmond
Issaquah

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.

Alternative routes for Belfast to Seattle

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

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.