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$635+ 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 2/3. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BFS
Jan 20 — Jan 271
Tue 1/20
Tue 1/27
1 adult, Economy
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Cheap flight deals from Seattle to Northern Ireland

Best flights from Seattle to Northern Ireland
Discover carefully curated flight deals from Seattle to Northern Ireland that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 21, 2025.

This Mytrip deal was found by Cheapflights users on 12/20. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/32:35 pmSEA - BFS
2 stops14h 50mMultiple Airlines
Tue 2/106:30 amBFS - SEA
2 stops18h 30mMultiple Airlines
Deal found 12/20$635
This Delta deal was found by Cheapflights users on 12/21. 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.
Sat 3/73:05 pmSEA - BHD
1 stop21h 55mDelta
Tue 3/176:30 amBHD - SEA
1 stop13h 05mDelta
Deal found 12/21$646
This KLM deal was found by Cheapflights users on 12/21. 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 4/15:30 pmSEA - BHD
1 stop15h 25mKLM
Wed 4/85:30 pmBHD - SEA
1 stop31h 00mKLM
Deal found 12/21$660
This Air France deal was found by Cheapflights users on 12/19. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/73:05 pmSEA - BHD
1 stop17h 45mMultiple Airlines
Wed 3/185:20 pmBHD - SEA
1 stop26h 15mMultiple Airlines
Deal found 12/19$646
This Delta deal was found by Cheapflights users on 12/21. 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.
Sat 3/73:05 pmSEA - BHD
1 stop21h 55mDelta
Wed 3/186:30 amBHD - SEA
2 stops20h 18mDelta
Deal found 12/21$656
This Air France deal was found by Cheapflights users on 12/19. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/73:05 pmSEA - BHD
1 stop17h 45mMultiple Airlines
Tue 3/176:30 amBHD - SEA
1 stop13h 05mMultiple Airlines
Deal found 12/19$646
This Mytrip deal was found by Cheapflights users on 12/19. 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.
Mon 2/22:35 pmSEA - BFS
2 stops21h 35mMultiple Airlines
Mon 2/96:30 amBFS - SEA
2 stops18h 30mMultiple Airlines
Deal found 12/19$718
This Mytrip deal was found by Cheapflights users on 12/20. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/307:00 pmSEA - BFS
2 stops20h 05mMultiple Airlines
Sat 5/98:15 pmBFS - SEA
3 stops27h 45mMultiple Airlines
Deal found 12/20$898
This Mytrip deal was found by Cheapflights users on 12/20. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/13:40 pmSEA - BFS
3 stops23h 40mMultiple Airlines
Sat 5/98:15 pmBFS - SEA
3 stops27h 45mMultiple Airlines
Deal found 12/20$984

Find 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 December 21, 2025.

Round-trip from

$635
(Mytrip)

Popular in

December

Cheapest in

April

Average price

$1,583
From Seattle/Tacoma Intl to Northern Ireland
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($128 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($59 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 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 December 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

Tue 2/3

2:35 pm-1:25 pm

2 stops14h 50m

Belfast Intl

Tue 2/10

6:30 am-5:00 pm

2 stops18h 30m

$635

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 3/7

3:05 pm-9:00 pm

1 stop21h 55m

Belfast City

Tue 3/17

6:30 am-12:35 pm

1 stop13h 05m

$646

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 3/7

3:05 pm-4:50 pm

1 stop17h 45m

Belfast City

Wed 3/18

5:20 pm-12:35 pm

1 stop26h 15m

$646

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 3/7

3:05 pm-4:50 pm

1 stop17h 45m

Belfast City

Tue 3/17

6:30 am-12:35 pm

1 stop13h 05m

$646

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 3/7

3:05 pm-9:00 pm

1 stop21h 55m

Belfast City

Wed 3/18

6:30 am-7:48 pm

2 stops20h 18m

$656

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 4/1

5:30 pm-4:55 pm

1 stop15h 25m

Belfast City

Wed 4/8

5:30 pm-4:30 pm

1 stop31h 00m

$660

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 2/2

2:35 pm-8:10 pm

2 stops21h 35m

Belfast Intl

Mon 2/9

6:30 am-5:00 pm

2 stops18h 30m

$718

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 4/30

7:00 pm-11:05 pm

2 stops20h 05m

Belfast Intl

Sat 5/9

8:15 pm-4:00 pm

3 stops27h 45m

$898

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 5/1

3:40 pm-11:20 pm

3 stops23h 40m

Belfast Intl

Sat 5/9

8:15 pm-4:00 pm

3 stops27h 45m

$984

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/20

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 December 21, 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.

How much does it cost to fly round-trip from Seattle to Northern Ireland?

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.

  • 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Seattle to Northern Ireland

See prices for flight routes from nearby airports that may be better suited for you.
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