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$632+ Cheap flights from Seattle (SEA) to Belfast

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 12/3. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BHD
dic. 6 — dic. 131
sáb. 12/6
sáb. 12/13
1 adult, Economy
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Cheap flight deals from Seattle to Belfast

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Belfast (BF1). 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 noviembre 6, 2025.

Round-trip from

$632
(Virgin Atlantic)

Popular in

December

Cheapest in

March

Average price

$807
From Seattle/Tacoma Intl to Belfast
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($95 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($34 potential savings vs. average RT price).
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Average for round-trip flights in November 2025
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Find flight deals from Seattle to Belfast

Cheapest flights from Seattle to Belfast
Explore the most affordable flight options available from Seattle to Belfast. Find the lowest fares from popular airlines and budget airlines, with prices last updated on noviembre 6, 2025.

This Delta deal was found by Cheapflights users on 11/5. 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.
mié. 12/33:05 pmSEA - BHD
1 stop21h 55mDelta
dom. 12/76:30 amBHD - SEA
1 stop13h 20mDelta
Deal found 11/5$632
This Virgin Atlantic deal was found by Cheapflights users on 11/4. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/33:05 pmSEA - BHD
1 stop17h 45mVirgin Atlantic
dom. 12/75:20 pmBHD - SEA
2 stops34h 53mVirgin Atlantic
Deal found 11/4$642
This British Airways deal was found by Cheapflights users on 11/6. 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.
mié. 12/36:50 pmSEA - BHD
1 stop28h 40mBritish Airways
dom. 12/78:25 pmBHD - SEA
1 stop28h 30mBritish Airways
Deal found 11/6$820
This Mytrip deal was found by Cheapflights users on 11/5. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/2010:05 amSEA - BFS
3 stops27h 35mMultiple Airlines
sáb. 12/2710:25 pmBFS - SEA
2 stops27h 55mMultiple Airlines
Deal found 11/5$2,464

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Belfast 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 noviembre 6, 2025.
Use the filters below to find and compare flights from Seattle to Belfast that are best for you.

Fly from

Seattle

Fly to

Belfast

Route

Depart

Return

Price

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

mié. 12/3

3:05 pm-4:50 pm

1 stop17h 45m

Belfast City

dom. 12/7

5:20 pm-11:50 am

1 stop26h 30m

$632

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

mié. 12/3

3:05 pm-9:00 pm

1 stop21h 55m

Belfast City

dom. 12/7

6:30 am-11:50 am

1 stop13h 20m

$632

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

vie. 3/27

2:35 pm-2:15 pm

1 stop16h 40m

Belfast City

mar. 3/31

9:35 am-11:35 am

1 stop34h 00m

$771

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

sáb. 3/7

1:35 pm-2:15 pm

1 stop16h 40m

Belfast City

mar. 3/17

6:35 am-12:30 pm

1 stop12h 55m

$773

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

sáb. 3/7

6:50 pm-7:40 pm

1 stop16h 50m

Belfast City

mié. 3/18

12:25 pm-5:55 pm

1 stop12h 30m

$791

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

sáb. 3/7

11:15 am-9:00 pm

2 stops25h 45m

Belfast City

mié. 3/18

6:30 am-12:35 pm

1 stop13h 05m

$796

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

mié. 12/3

6:50 pm-7:30 am

1 stop28h 40m

Belfast City

dom. 12/7

8:25 pm-4:55 pm

1 stop28h 30m

$820

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

sáb. 12/20

10:05 am-9:40 pm

3 stops27h 35m

Belfast Intl

sáb. 12/27

10:25 pm-6:20 pm

2 stops27h 55m

$2,464

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/4

Best time to book a flight from Seattle to Belfast

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

What is the cheapest time of day to fly from SEA to BFS?

Find hourly flight availability from Seattle to Belfast. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated noviembre 6, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Belfast in the morning. If you’re flexible enough to do this you can expect to save up to 8% on your trip compared to booking a flight in the afternoon.

Reviews of airlines servicing Belfast

Get insights into the airlines that provide service to Belfast. 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 Belfast. Reviews last updated noviembre 6, 2025.
Read reviews from past customers who have flown British Airways from Seattle to Belfast. 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.
British Airways
6.7
Okay
7,500 reviews

Food

6.3

Entertainment

6.4

Comfort

6.7

Crew

7.6

Boarding

6.9

Overall

6.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2025

IAD - LHR

The plane had to load and unload passengers not through a jet way but out on the tarmac at Heathrow. The steps were steep. We weren't expecting to have to carry our luggage up and down stairs.
British Airways
6.7
Okay
7,500 reviews
British Airways
6.7
Okay
7,500 reviews

Food

6.3

Entertainment

6.4

Comfort

6.7

Crew

7.6

Boarding

6.9

Overall

6.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2025

IAD - LHR

The plane had to load and unload passengers not through a jet way but out on the tarmac at Heathrow. The steps were steep. We weren't expecting to have to carry our luggage up and down stairs.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Belfast. 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 from for flights from Seattle to Belfast?

    If you book a flight to Belfast from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 0 flights from Seattle/Tacoma Intl to Belfast per day from 1 airline.

  • How long is the flight from Seattle to Belfast?

    Airlines like Virgin Atlantic and Delta fly from Seattle to Belfast in about 17h 45m. The time it takes to get you to your destination can typically vary by up to 4h 10m. The distance between Seattle and Belfast is about 4472 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What is the cheapest airline to fly from Seattle to Belfast round-trip?

    Flying on British Airways is currently your cheapest option to Belfast, with prices starting at $737. British Airways is 18% cheaper than the average price of flights available within the next 90 days to this destination.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Seattle to Belfast 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

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Alternative routes for Seattle to Belfast

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

Top airline flying from Seattle to Belfast

Discover the top airline that operate flights from Seattle to Belfast. 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 2,558,603 searches. Data last updated noviembre 6, 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$737Average$951FlexibilityNo cancel feeOn-time70%

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