In terms of precipitation, rainfall in Northern Ireland ranges from 50.0 - 90.0 inches per month. October is typically the wettest month, when rainfall can reach 90.0 mm. April is typically the driest time to visit Northern Ireland when rainfall is around 50.0 mm.

If weather is an important factor for your trip to Northern Ireland, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 16.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 5.0 C).

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

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Seattle to Northern Ireland as you normally would.

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.

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.

£475+ Flights from Seattle to Northern Ireland

Cheap flight deals from Seattle to Northern Ireland

Enter your travel dates to find the best prices.

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

Tue 3/214:35SEA - BFS

2 stops14h 50mMultiple Airlines

Tue 10/206:30BFS - SEA

2 stops18h 30mMultiple Airlines

Deal found 20/12£475

Sat 7/315:05SEA - BHD

1 stop21h 55mDelta

Tue 17/306:30BHD - SEA

1 stop13h 05mDelta

Deal found 21/12£483

Wed 1/417:30SEA - BHD

1 stop15h 25mKLM

Wed 8/417:30BHD - SEA

1 stop31h 00mKLM

Deal found 21/12£493

Sat 7/315:05SEA - BHD

1 stop17h 45mMultiple Airlines

Wed 18/317:20BHD - SEA

1 stop26h 15mMultiple Airlines

Deal found 19/12£483

Sat 7/315:05SEA - BHD

1 stop21h 55mDelta

Wed 18/306:30BHD - SEA

2 stops20h 18mDelta

Deal found 21/12£490

Sat 7/315:05SEA - BHD

1 stop17h 45mMultiple Airlines

Tue 17/306:30BHD - SEA

1 stop13h 05mMultiple Airlines

Deal found 19/12£483

Mon 2/214:35SEA - BFS

2 stops21h 35mMultiple Airlines

Mon 9/206:30BFS - SEA

2 stops18h 30mMultiple Airlines

Deal found 19/12£537

Thu 30/419:00SEA - BFS

2 stops20h 05mMultiple Airlines

Sat 9/520:15BFS - SEA

3 stops27h 45mMultiple Airlines

Deal found 20/12£671

Fri 1/515:40SEA - BFS

3 stops23h 40mMultiple Airlines

Sat 9/520:15BFS - SEA

3 stops27h 45mMultiple Airlines

Deal found 20/12£735

Find flight deals from Seattle to Northern Ireland

Round-trip from	£451
Popular in	December
Cheapest in	April
Average price	£1,183

British Airways
7/3-17/3
2 total stops
33h 00m total
Seattle to Northern Ireland

Search Deals

Highest demand for flights based on searches. 11% potential increase in price (£71 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease (£34 potential savings vs. average return price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Cheapflights Fare Finder

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

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Tue 3/2

14:35-13:25

2 stops14h 50m

Belfast Intl

Tue 10/2

06:30-17:00

2 stops18h 30m

£475

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 7/3

15:05-21:00

1 stop21h 55m

Belfast City

Tue 17/3

06:30-12:35

1 stop13h 05m

£483

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 7/3

15:05-16:50

1 stop17h 45m

Belfast City

Wed 18/3

17:20-12:35

1 stop26h 15m

£483

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 7/3

15:05-16:50

1 stop17h 45m

Belfast City

Tue 17/3

06:30-12:35

1 stop13h 05m

£483

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sat 7/3

15:05-21:00

1 stop21h 55m

Belfast City

Wed 18/3

06:30-19:48

2 stops20h 18m

£490

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 1/4

17:30-16:55

1 stop15h 25m

Belfast City

Wed 8/4

17:30-16:30

1 stop31h 00m

£493

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Mon 2/2

14:35-20:10

2 stops21h 35m

Belfast Intl

Mon 9/2

06:30-17:00

2 stops18h 30m

£537

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Thu 30/4

19:00-23:05

2 stops20h 05m

Belfast Intl

Sat 9/5

20:15-16:00

3 stops27h 45m

£671

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 1/5

15:40-23:20

3 stops23h 40m

Belfast Intl

Sat 9/5

20:15-16:00

3 stops27h 45m

£735

Flights are sorted by cheapest return flights first.

Deals found on 20/12

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

No data available for this route at this time. Please check back soon.

Related info for your journey

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.
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

Browse thousands of different options on Cheapflights for your next trip

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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.

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Cheap flights from Seattle to Northern Ireland from £475

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/2. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Seattle to Northern Ireland

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

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

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 21 December 2025.

Round-trip from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

Use the filters below to find and compare flights from Seattle to Northern Ireland that are best for you.

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.

Cheapflights Insights

Everything you need to know about your 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?

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

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

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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Seattle to Northern Ireland

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

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

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

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

Can Cheapflights 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?

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Book with Flexibility

Travel Smart

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