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Cheap flights from Seattle to Northern Ireland from £203

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 16/4. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — BFS
24 Apr — 1 May1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Seattle to Northern Ireland

Enter your travel dates to find the best prices.

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 25 March 2026.

Thu 7/519:00
SEA
-
BFS
3 stops18h 30m
Multiple Airlines
Sat 16/520:15
BFS
-
SEA
3 stops45h 25m
Multiple Airlines
Deal found 20/3£578
Fri 17/419:00
SEA
-
BFS
3 stops20h 20m
Multiple Airlines
Sun 3/522:10
BFS
-
SEA
3 stops43h 30m
Multiple Airlines
Deal found 25/3£608
Mon 5/1020:20
SEA
-
BHD
1 stop15h 05m
British Airways
Thu 22/1012:45
BHD
-
SEA
1 stop13h 40m
British Airways
Deal found 25/3£627
Sun 27/920:20
SEA
-
BHD
1 stop16h 15m
British Airways
Thu 1/1016:35
BHD
-
SEA
1 stop27h 00m
British Airways
Deal found 20/3£639
Fri 8/519:00
SEA
-
BHD
2 stops17h 30m
Multiple Airlines
Fri 15/507:00
BHD
-
SEA
2 stops21h 40m
Multiple Airlines
Deal found 24/3£675
Fri 2/1020:20
SEA
-
BHD
1 stop13h 50m
British Airways
Tue 6/1020:25
BHD
-
SEA
1 stop23h 10m
British Airways
Deal found 24/3£676
Wed 6/519:00
SEA
-
BFS
2 stops14h 05m
Multiple Airlines
Wed 13/507:35
BFS
-
SEA
2 stops21h 05m
Multiple Airlines
Deal found 22/3£690
Wed 27/515:40
SEA
-
BFS
3 stops24h 25m
Multiple Airlines
Mon 1/606:10
BFS
-
SEA
2 stops22h 30m
Multiple Airlines
Deal found 21/3£716
Fri 8/520:20
SEA
-
BHD
1 stop16h 15m
British Airways
Fri 15/506:30
BHD
-
SEA
1 stop13h 05m
British Airways
Deal found 24/3£717
Wed 29/420:20
SEA
-
BHD
1 stop15h 30m
British Airways
Sun 3/520:10
BHD
-
SEA
1 stop23h 25m
British Airways
Deal found 20/3£721
Wed 27/513:30
SEA
-
BHD
1 stop16h 05m
British Airways
Mon 1/619:35
BHD
-
SEA
1 stop24h 00m
British Airways
Deal found 21/3£759
Fri 3/415:40
SEA
-
BFS
3 stops21h 05m
Multiple Airlines
Sun 12/406:25
BFS
-
SEA
3 stops42h 50m
Multiple Airlines
Deal found 22/3£1,049

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 25 March 2026.

Round-trip from

£578

One-way from

£203

Popular in

December

Cheapest in

October

Average price

£613
7/5-16/5
  • 7/5-16/5
  • 6 total stops
  • 63h 55m total
  • Seattle to Northern Ireland
Search Deals
16/4
  • 16/4
  • 3 total stops
  • 44h 20m total
  • Seattle to Northern Ireland
Search Deals
Highest demand for flights based on searches. 14% potential increase in price (£96 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease (£32 potential savings vs. average return price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customise 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 858,174 searches. Data last updated 25 March 2026.
Use the filters below to find and compare flights from Seattle to Northern Ireland that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 7/5

19:00-21:30

3 stops18h 30m

Belfast Intl

Sat 16/5

20:15-09:40

3 stops45h 25m

£578

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 17/4

19:00-23:20

3 stops20h 20m

Belfast Intl

Sun 3/5

22:10-09:40

3 stops43h 30m

£608

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Fri 8/5

19:00-20:30

2 stops17h 30m

Belfast City

Fri 15/5

07:00-20:40

2 stops21h 40m

£675

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Wed 6/5

19:00-17:05

2 stops14h 05m

Belfast Intl

Wed 13/5

07:35-20:40

2 stops21h 05m

£690

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 29/4

20:20-19:50

1 stop15h 30m

Belfast City

Sun 3/5

20:10-11:35

1 stop23h 25m

£721

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 7/5

07:15-09:20

2 stops18h 05m

Belfast City

Sat 16/5

17:30-16:30

1 stop31h 00m

£775

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 7/5

11:16-19:25

2 stops24h 09m

Belfast City

Sat 16/5

07:05-22:38

2 stops23h 33m

£784

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 16/4

20:20-19:25

1 stop15h 05m

Belfast City

Sun 3/5

20:10-11:35

1 stop23h 25m

£804

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 27/5

15:40-21:05

3 stops21h 25m

Belfast City

Mon 1/6

07:00-22:43

3 stops23h 43m

£814

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Thu 16/4

07:15-09:20

2 stops18h 05m

Belfast City

Sun 3/5

09:50-23:54

2 stops22h 04m

£850

Flights are sorted by cheapest return flights first.

Deals found on 22/3

Showing 1-10 of 18 resultsSorted by cheapest first
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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 return 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

How much does it cost for a return flight 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?

    Located just 11.4 mi from the city center, Seattle/Tacoma Intl (SEA) is the airport most travelers will use when flying to Northern Ireland from Seattle.

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

    British Airways and KLM can get you from Seattle to Northern Ireland in just under 15h 30m. Your travel time can differ by up to 2h 35m. There are 4472 mi between Seattle and Northern Ireland. 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 holiday 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

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How does Cheapflights help users find flights from Seattle to Northern Ireland?

Deals for Seattle to Northern Ireland flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Seattle to Northern Ireland?

Cheapflights simply makes it quick and affordable to book flights from Seattle to Northern Ireland by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

Can Cheapflights find flights from Seattle to Northern Ireland with no change fees?

Yes! Cheapflights helps users easily find flights from Seattle to Northern Ireland with no change fees.

Can Cheapflights notify me if prices for flights from Seattle to Northern Ireland become cheaper?

Not ready to book yet? You can track prices for flights from Seattle to Northern Ireland on Cheapflights with our Price Alert feature and get notified when better prices are available.

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