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$638+ Cheap flights from Seattle (SEA) to Northern Ireland

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 — BFS
Nov 19 — Nov 261
Wed 11/19
Wed 11/26
1 adult, Economy
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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 October 20, 2025.

This Mytrip deal was found by Cheapflights users on 10/19. 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 12/32:35 pmSEA - BFS
2 stops19h 20mMultiple Airlines
Wed 12/106:30 amBFS - SEA
2 stops18h 30mMultiple Airlines
Deal found 10/19$638
This British Airways deal was found by Cheapflights users on 10/19. 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 12/75:35 pmBHD - SEA
1 stop31h 20mBritish Airways
Deal found 10/19$666
This Delta deal was found by Cheapflights users on 10/17. 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 12/75:20 pmBHD - SEA
1 stop26h 30mDelta
Deal found 10/17$689
This KAYAK deal was found by Cheapflights users on 10/20. 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 10/299:05 pmSEA - BHD
2 stops27h 25mBritish Airways
Wed 11/56:35 amBHD - SEA
2 stops19h 45mBritish Airways
Deal found 10/20$1,034
This Mytrip deal was found by Cheapflights users on 10/18. 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.
Sat 11/82:00 pmSEA - BFS
2 stops16h 40mMultiple Airlines
Sat 11/1510:25 pmBFS - SEA
2 stops31h 51mMultiple Airlines
Deal found 10/18$1,171
This Cheapflightsfares deal was found by Cheapflights users on 10/18. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/91:25 pmSEA - BHD
1 stop14h 05mBritish Airways
Sat 12/206:00 pmBHD - SEA
2 stops35h 11mBritish Airways
Deal found 10/18$4,166

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 October 20, 2025.

Round-trip from

$638
(Mytrip)

Popular in

December

Cheapest in

March

Average price

$776
From Seattle/Tacoma Intl to Northern Ireland
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($95 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($34 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

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 October 20, 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 12/3

2:35 pm-5:55 pm

2 stops19h 20m

Belfast Intl

Wed 12/10

6:30 am-5:00 pm

2 stops18h 30m

$638

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 12/3

6:50 pm-4:35 pm

1 stop13h 45m

Belfast City

Sun 12/7

5:35 pm-4:55 pm

1 stop31h 20m

$666

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 12/3

7:20 am-9:00 pm

2 stops29h 40m

Belfast City

Sun 12/7

5:20 pm-11:50 am

1 stop26h 30m

$689

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 10/29

9:05 pm-7:30 am

2 stops27h 25m

Belfast City

Wed 11/5

6:35 am-6:20 pm

2 stops19h 45m

$1,034

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Sat 11/8

2:00 pm-2:40 pm

2 stops16h 40m

Belfast Intl

Sat 11/15

10:25 pm-10:16 pm

2 stops31h 51m

$1,171

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/19

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 October 20, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 8% on flights from Seattle to Northern Ireland by exploring options for tickets in the morning.

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 October 20, 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
7,461 reviews

Crew

7.6

Comfort

6.7

Entertainment

6.4

Overall

6.7

Boarding

6.9

Food

6.3

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
7,461 reviews
British Airways
6.7
Okay
7,461 reviews

Crew

7.6

Comfort

6.7

Entertainment

6.4

Overall

6.7

Boarding

6.9

Food

6.3

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 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 Delta 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 15h 55m. 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.

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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 October 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$737Average$951FlexibilityNo cancel feeOn-time70%

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