Cheap flights from Northern Ireland to Seattle from £343

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Northern Ireland to Seattle departing on 21/10. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Find the cheapest flights from Northern Ireland to Seattle

Cheap return flights

 Logo
06:35 - 20:40BFS-SEA
22h 05m2 stops
 Logo
19:00 - 23:00SEA-BFS
20h 00m2 stops
Thu, 9 Oct - Mon, 13 Oct
 Logo
06:35 - 15:30BFS-SEA
16h 55m1 stop
 Logo
17:35 - 20:35SEA-BFS
19h 00m1 stop
Thu, 9 Oct - Mon, 13 Oct
 Logo
07:05 - 20:40BHD-SEA
21h 35m2 stops
 Logo
19:00 - 20:25SEA-BHD
17h 25m2 stops
Thu, 9 Oct - Mon, 13 Oct
American Airlines Logo
09:05 - 16:55BHD-SEA
15h 50m1 stop
American Airlines Logo
13:48 - 14:15SEA-BHD
17h 27m2 stops
£554American Airlines
Find Deal
Thu, 5 Mar - Mon, 9 Mar
American Airlines Logo
06:35 - 16:55BHD-SEA
18h 20m1 stop
American Airlines Logo
13:48 - 14:15SEA-BHD
17h 27m2 stops
£555American Airlines
Find Deal
Thu, 5 Mar - Mon, 9 Mar
British Airways Logo
20:00 - 11:30BHD-SEA
23h 30m1 stop
British Airways Logo
19:50 - 18:35SEA-BHD
15h 45m1 stop
£557British Airways
Find Deal
Thu, 5 Mar - Mon, 9 Mar
American Airlines Logo
10:40 - 23:07BHD-SEA
20h 27m2 stops
American Airlines Logo
13:48 - 14:15SEA-BHD
17h 27m2 stops
£559American Airlines
Find Deal
Thu, 5 Mar - Mon, 9 Mar
Delta Logo
06:30 - 11:50BHD-SEA
13h 20m1 stop
Delta Logo
14:10 - 21:15SEA-BHD
23h 05m1 stop
£567Delta
Find Deal
Thu, 9 Oct - Mon, 13 Oct
 Logo
06:35 - 20:40BFS-SEA
22h 05m2 stops
 Logo
20:25 - 20:35SEA-BFS
16h 10m1 stop
Thu, 9 Oct - Mon, 13 Oct
 Logo
17:25 - 20:40BHD-SEA
35h 15m2 stops
 Logo
05:30 - 17:40SEA-BHD
28h 10m3 stops
Thu, 9 Oct - Mon, 13 Oct

Delta flights from Northern Ireland to Seattle

Our best Delta deals on Northern Ireland to Seattle flight tickets
Delta
15 Sept
BHD06:30Belfast City
20h 30m
2 stops
SEA19:00Seattle/Tacoma Intl
24 Sept
SEA17:40Seattle/Tacoma Intl
15h 15m
1 stop
BHD16:55Belfast City
Delta
15 Sept
BHD06:30Belfast City
20h 30m
2 stops
SEA19:00Seattle/Tacoma Intl
24 Sept
SEA09:40Seattle/Tacoma Intl
23h 15m
2 stops
BHD16:55Belfast City
Delta
9 Oct
BHD06:30Belfast City
13h 20m
1 stop
SEA11:50Seattle/Tacoma Intl
13 Oct
SEA14:10Seattle/Tacoma Intl
23h 05m
1 stop
BHD21:15Belfast City

American Airlines flights from Northern Ireland to Seattle

Our best American Airlines deals on Northern Ireland to Seattle flight tickets
American Airlines
5 Mar
BHD09:05Belfast City
15h 50m
1 stop
SEA16:55Seattle/Tacoma Intl
9 Mar
SEA13:48Seattle/Tacoma Intl
17h 27m
2 stops
BHD14:15Belfast City
American Airlines
5 Mar
BHD06:35Belfast City
18h 20m
1 stop
SEA16:55Seattle/Tacoma Intl
9 Mar
SEA13:48Seattle/Tacoma Intl
17h 27m
2 stops
BHD14:15Belfast City
American Airlines
5 Mar
BHD10:40Belfast City
20h 27m
2 stops
SEA23:07Seattle/Tacoma Intl
9 Mar
SEA13:48Seattle/Tacoma Intl
17h 27m
2 stops
BHD14:15Belfast City

momondo Fare Finder

 
Customise your flight search to find flights from Northern Ireland to Seattle 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, momondo users made 279,928 searches. Data last updated 9 September 2025.
Use the filters below to find and compare flights from Northern Ireland to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 9/10

06:35-20:40

2 stops22h 05m

Seattle/Tacoma Intl

Mon 13/10

19:00-23:00

2 stops20h 00m

£485

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 9/10

06:35-15:30

1 stop16h 55m

Seattle/Tacoma Intl

Mon 13/10

17:35-20:35

1 stop19h 00m

£539

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 9/10

07:05-20:40

2 stops21h 35m

Seattle/Tacoma Intl

Mon 13/10

19:00-20:25

2 stops17h 25m

£541

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/3

09:05-16:55

1 stop15h 50m

Seattle/Tacoma Intl

Mon 9/3

13:48-14:15

2 stops17h 27m

£554

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/3

06:35-16:55

1 stop18h 20m

Seattle/Tacoma Intl

Mon 9/3

13:48-14:15

2 stops17h 27m

£555

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/3

20:00-11:30

1 stop23h 30m

Seattle/Tacoma Intl

Mon 9/3

19:50-18:35

1 stop15h 45m

£557

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 5/3

10:40-23:07

2 stops20h 27m

Seattle/Tacoma Intl

Mon 9/3

13:48-14:15

2 stops17h 27m

£559

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 9/10

06:30-11:50

1 stop13h 20m

Seattle/Tacoma Intl

Mon 13/10

14:10-21:15

1 stop23h 05m

£567

BelfastSeattle

BFS - SEA

BFSSEA

Belfast Intl

Thu 9/10

06:35-20:40

2 stops22h 05m

Seattle/Tacoma Intl

Mon 13/10

20:25-20:35

1 stop16h 10m

£804

BelfastSeattle

BHD - SEA

BHDSEA

Belfast City

Thu 9/10

17:25-20:40

2 stops35h 15m

Seattle/Tacoma Intl

Mon 13/10

05:30-17:40

3 stops28h 10m

£944

Flights are sorted by cheapest return flights first.

Showing 1-10 of 17 resultsSorted by cheapest first
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See travel insights to Seattle from

How to get the cheapest flight ticket from Northern Ireland to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest airline that flies from Northern Ireland to Seattle/Tacoma Intl?

Aer Lingus and British Airways are the most popular carriers operating from Northern Ireland to Seattle/Tacoma Intl

Cheap Northern Ireland to Seattle flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Northern Ireland to Seattle

Direct flights

None
There are no direct flights from Northern Ireland to Seattle. There are no popular flight routes from Northern Ireland to Seattle.
  • When did momondo last update prices for flights from Northern Ireland to Seattle/Tacoma Intl Airport?

    Prices for flights from Northern Ireland to Seattle/Tacoma Intl Airport refresh daily.

  • How many operators does momondo search for flights from Northern Ireland to Seattle/Tacoma Intl Airport?

  • How old do you have to be to fly from Northern Ireland to Seattle/Tacoma Intl Airport?

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Northern Ireland to Seattle/Tacoma Intl Airport.

  • What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

    The travel and health documents required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

Best airlines flying from Northern Ireland to Seattle

Compare and see reviews for airlines that fly from Northern Ireland to Seattle with momondo
Airline
Rating
Free Cancellation
Price
British AirwaysPriceFrom £435Free CancellationRating
6.7
7,358 reviews
Search British Airways flights
American AirlinesPriceFrom £555Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Fife
Tukwila
Renton
SeaTac

Why use momondo?

Why should I use momondo to find a flight deal from Northern Ireland to Seattle?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Northern Ireland to Seattle. momondo saves you time and could save you money on your trip.

Can I find flights from Northern Ireland to Seattle with flexible booking policies on momondo?

momondo does allow users to show only those flights to Seattle from Northern Ireland which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from Northern Ireland to Seattle?

momondo helps you find the best flight between Northern Ireland and Seattle by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

I’m not ready to book a flight from Northern Ireland to Seattle right now. Can momondo alert me if prices change?

Price alerts on flights to Seattle from Northern Ireland are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.

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1 adult
Thu 9/10
Thu 16/10

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