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Northern Ireland

$307+ Cheap flights from Seattle (SEA) to Northern Ireland

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 10/7. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BFS
Aug 26 — Sep 21
Tue 8/26
Tue 9/2
1 adult, Economy
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Cheap flight deals from Seattle to Northern Ireland

Keep the following information in mind while searching for Seattle to Northern Ireland flight deals. Data was last updated August 21, 2025.

Round-trip from

$725
(Mytrip)

One-way from

$307
(Kiwi.com)

Popular in

July

Cheapest in

March

Average price

$844
From Seattle/Tacoma Intl to Northern Ireland
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One-way flight from Seattle/Tacoma Intl to Northern Ireland
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Highest demand for flights based on searches. 9% potential increase in price ($92 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($25 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Find flight deals from Seattle to Northern Ireland

Cheapest flights from Seattle to Northern Ireland
Explore the most affordable flight options available from Seattle to Northern Ireland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 21, 2025.

This Mytrip deal was found by Cheapflights users on 8/21. 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.
Wed 9/107:35 pmSEA - BFS
2 stops15h 00mMultiple Airlines
Wed 9/175:45 amBFS - SEA
2 stops20h 05mMultiple Airlines
Deal found 8/21$725
This KAYAK deal was found by Cheapflights users on 8/21. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/297:50 pmSEA - BHD
1 stop13h 45mBritish Airways
Wed 11/59:15 amBHD - SEA
1 stop15h 40mBritish Airways
Deal found 8/21$750
This British Airways deal was found by Cheapflights users on 8/21. 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.
Wed 12/36:50 pmSEA - BHD
1 stop13h 45mBritish Airways
Sun 12/76:30 amBHD - SEA
1 stop18h 25mBritish Airways
Deal found 8/21$780
This KLM deal was found by Cheapflights users on 8/21. 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.
Wed 9/105:40 pmSEA - BHD
1 stop19h 35mKLM
Wed 9/176:30 amBHD - SEA
1 stop13h 15mKLM
Deal found 8/21$816
This FlightHub deal was found by Cheapflights users on 8/21. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/107:45 amSEA - BHD
2 stops20h 10mBritish Airways
Wed 9/178:15 pmBHD - SEA
2 stops31h 54mBritish Airways
Deal found 8/21$844
This Delta deal was found by Cheapflights users on 8/21. 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.
Wed 12/37:20 amSEA - BHD
2 stops29h 40mDelta
Sun 12/76:30 amBHD - SEA
1 stop13h 20mDelta
Deal found 8/21$870

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Northern Ireland 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 August 21, 2025.
Use the filters below to find and compare flights from Seattle to Northern Ireland that are best for you.

Fly from

Seattle

Fly to

Northern Ireland

Route

Depart

Return

Price

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Wed 9/10

7:35 pm-6:35 pm

2 stops15h 00m

Belfast Intl

Wed 9/17

5:45 am-5:50 pm

2 stops20h 05m

$725

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 10/29

7:50 pm-4:35 pm

1 stop13h 45m

Belfast City

Wed 11/5

9:15 am-4:55 pm

1 stop15h 40m

$750

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 12/3

6:50 pm-4:35 pm

1 stop13h 45m

Belfast City

Sun 12/7

6:30 am-4:55 pm

1 stop18h 25m

$780

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 9/10

5:40 pm-9:15 pm

1 stop19h 35m

Belfast City

Wed 9/17

6:30 am-11:45 am

1 stop13h 15m

$816

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 9/10

7:45 am-11:55 am

2 stops20h 10m

Belfast City

Wed 9/17

8:15 pm-8:09 pm

2 stops31h 54m

$844

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 12/3

7:20 am-9:00 pm

2 stops29h 40m

Belfast City

Sun 12/7

6:30 am-11:50 am

1 stop13h 20m

$870

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 10/7

1:40 pm-6:35 pm

3 stops44h 55m

$307

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Tue 10/7

2:35 pm-3:05 pm

2 stops40h 30m

$338

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Tue 10/7

8:20 pm-5:30 pm

1 stop13h 10m

$429

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/20

Best time to book a flight from Seattle to Northern Ireland

Have a flexible travel schedule? Discover the best time to fly to Northern Ireland 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 Northern Ireland

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

Find hourly flight availability from Seattle to Northern Ireland. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 21, 2025.

When flying from Seattle to Northern Ireland, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Reviews of airlines servicing Northern Ireland

Get insights into the airlines that provide service to Northern Ireland. 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 Northern Ireland. Reviews last updated August 21, 2025.
Read reviews from past customers who have flown British Airways from Seattle to Northern Ireland. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
British Airways
6.7
Okay
7,291 reviews

Overall

6.7

Crew

7.6

Comfort

6.7

Entertainment

6.4

Boarding

6.9

Food

6.3

Reviews

1 / 20
4.0
Okay

Anonymous,May 2025

LAX - LHR

Entertainment system did not work. Seems like Wi-Fi should have been comped at hat point. Boarding at Marco Polo in Venice was terrible. Insisted on gate checking our bag but not others! Connection was confused and flight was very late.
British Airways
6.7
Okay
7,291 reviews
British Airways
6.7
Okay
7,291 reviews

Overall

6.7

Crew

7.6

Comfort

6.7

Entertainment

6.4

Boarding

6.9

Food

6.3

Reviews

1 / 20
4.0
Okay

Anonymous,May 2025

LAX - LHR

Entertainment system did not work. Seems like Wi-Fi should have been comped at hat point. Boarding at Marco Polo in Venice was terrible. Insisted on gate checking our bag but not others! Connection was confused and flight was very late.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Northern Ireland. 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 Northern Ireland?

    Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly out of when you book flights from Seattle to Northern Ireland.

  • How long is the flight from Seattle to Northern Ireland?

    Airlines like British Airways and KLM fly from Seattle to Northern Ireland in about 13h 45m. The time it takes to get you to your destination can typically vary by up to 5h 50m. The distance from Seattle to Northern Ireland is about 4472 mi. This flight may include one or multiple stops.

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

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

  • How can I find direct flights from Seattle to Northern Ireland?

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

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

    Yes. Cheapflights offers flight deals from Seattle to Northern Ireland 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 Seattle to Northern Ireland?

    Currently, February is the cheapest month in which you can book a flight from Seattle to Northern Ireland (average of $657). Flying from Seattle to Northern Ireland in June is currently the most expensive (average of $1,189). 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.

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Alternative routes for Seattle to Northern Ireland

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Top airline flying from Seattle to Northern Ireland

Discover the top airline that operate flights from Seattle to Northern Ireland. 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 August 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$701Average$866FlexibilityNo cancel feeOn-time70%

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