What is the cheapest month to book a flight from Seattle to Northern Ireland?

Currently, January is the cheapest month in which you can book a flight from Seattle to Northern Ireland (average of £67). Flying from Seattle to Northern Ireland in July is currently the most expensive (average of £90). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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 month to fly from Seattle to Northern Ireland?

The best pricing can be found in the month of March. Prices to Northern Ireland from Seattle average £689. You can even find prices in March for less than £689, as users have found deals to Northern Ireland from as low as £514. The month of August appears to be one of the more expensive times to travel to Northern Ireland from Seattle. Flying in the targeted month can save you up to 47%.

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.

£570+ Flights from Seattle to Northern Ireland

Cheap flight deals from Seattle to Northern Ireland

Round-trip from	£570
Popular in	August
Cheapest in	March
Average price	£833

British Airways
3/12-7/12
2 total stops
32h 10m total
Seattle to Northern Ireland

Search Deals

Highest demand for flights based on searches. 19% potential increase in price (£120 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 5% potential price decrease (£27 potential savings vs. average return price).

Search Deals

Average for round-trip flights in July 2025

Search Deals

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 2 July 2025.

Wed 3/1218:50SEA - BHD

1 stop13h 45mBritish Airways

Sun 7/1206:30BHD - SEA

1 stop18h 25mBritish Airways

Deal found 29/6£570

Wed 3/1215:00SEA - BHD

1 stop22h 00mDelta

Sun 7/1206:30BHD - SEA

1 stop13h 20mDelta

Deal found 1/7£625

Fri 15/815:45SEA - BFS

2 stops16h 55mMultiple Airlines

Fri 22/809:50BFS - SEA

2 stops18h 50mMultiple Airlines

Deal found 1/7£642

Sun 23/1115:40SEA - BHD

2 stops17h 10mMultiple Airlines

Sun 30/1109:10BHD - SEA

2 stops18h 06mMultiple Airlines

Deal found 29/6£684

Fri 18/717:35SEA - BHD

1 stop19h 40mKLM

Fri 25/717:25BHD - SEA

1 stop30h 25mKLM

Deal found 1/7£836

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 2 July 2025.

Wed 3/1218:50SEA - BHD

1 stop13h 45mBritish Airways

Sun 7/1206:30BHD - SEA

1 stop18h 25mBritish Airways

Deal found 29/6£570

Wed 3/1215:00SEA - BHD

1 stop22h 00mDelta

Sun 7/1206:30BHD - SEA

1 stop13h 20mDelta

Deal found 1/7£625

Fri 15/815:45SEA - BFS

2 stops16h 55mMultiple Airlines

Fri 22/809:50BFS - SEA

2 stops18h 50mMultiple Airlines

Deal found 1/7£642

Fri 18/717:35SEA - BHD

1 stop19h 40mKLM

Fri 25/717:25BHD - SEA

1 stop30h 25mKLM

Deal found 1/7£836

Sun 23/1115:40SEA - BHD

2 stops17h 10mMultiple Airlines

Sun 30/1109:10BHD - SEA

2 stops18h 06mMultiple Airlines

Deal found 29/6£684

Last-minute flights from Seattle to Northern Ireland
Discover last-minute flight deals from Seattle to Northern Ireland. Data last updated 2 July 2025 and is based on user searches.

Fri 18/713:30SEA - BHD

1 stop11h 55mBritish Airways

Fri 25/706:35BHD - SEA

2 stops26h 08mBritish Airways

Deal found 1/7£769

Fri 18/717:35SEA - BHD

1 stop19h 40mKLM

Fri 25/717:25BHD - SEA

1 stop30h 25mKLM

Deal found 1/7£836

Fri 18/705:30SEA - BHD

3 stops30h 55mMultiple Airlines

Fri 25/711:00BHD - SEA

3 stops35h 50mMultiple Airlines

Deal found 1/7£877

Fri 15/815:45SEA - BFS

2 stops16h 55mMultiple Airlines

Fri 22/809:50BFS - SEA

2 stops18h 50mMultiple Airlines

Deal found 1/7£642

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 - BHD

SEABHD

Seattle/Tacoma Intl

Wed 3/12

18:50-16:35

1 stop13h 45m

Belfast City

Sun 7/12

06:30-16:55

1 stop18h 25m

£570

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Wed 3/12

15:00-21:00

1 stop22h 00m

Belfast City

Sun 7/12

06:30-11:50

1 stop13h 20m

£625

SeattleBelfast

SEA - BFS

SEABFS

Seattle/Tacoma Intl

Fri 15/8

15:45-16:40

2 stops16h 55m

Belfast Intl

Fri 22/8

09:50-20:40

2 stops18h 50m

£642

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Sun 23/11

15:40-16:50

2 stops17h 10m

Belfast City

Sun 30/11

09:10-19:16

2 stops18h 06m

£684

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Fri 18/7

17:35-21:15

1 stop19h 40m

Belfast City

Fri 25/7

17:25-15:50

1 stop30h 25m

£836

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Mon 27/10

15:35-17:25

2 stops18h 50m

£933

SeattleBelfast

SEA - BHD

SEABHD

Seattle/Tacoma Intl

Mon 27/10

19:50-18:35

1 stop15h 45m

£1,253

Flights are sorted by cheapest return flights first.

Deals found on 1/7

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.

Reviews of airlines servicing Northern Ireland

Read through reviews of airlines operating flights from Seattle to Northern Ireland, such as Delta, KLM, andBritish Airways. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very Good

7,975 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Delta

8.0

Very Good

7,975 reviews

Delta

8.0

Very Good

7,975 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

KLM

7.8

Good

1,366 reviews

Delta

8.0

Very Good

7,975 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

British Airways

6.6

Okay

7,086 reviews

Delta

8.0

Very Good

7,975 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

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.
What is the cheapest month to book a flight from Seattle to Northern Ireland?
Currently, January is the cheapest month in which you can book a flight from Seattle to Northern Ireland (average of £67). Flying from Seattle to Northern Ireland in July is currently the most expensive (average of £90). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Alternative routes for Seattle to Northern Ireland

Seattle to Heathrow flights

Seattle to Gatwick flights

Seattle to London City flights

Portland to Heathrow flights

Portland to Gatwick flights

Seattle to Edinburgh flights

Portland to Edinburgh flights

Seattle to Glasgow Intl flights

Seattle to Manchester flights

Portland to Luton flights

Portland to Stansted flights

Spokane to Heathrow flights

Spokane to Edinburgh flights

Portland to Manchester flights

Spokane to Gatwick flights

Seattle to Birmingham flights

Portland to Glasgow Intl flights

Spokane to Glasgow Intl flights

Seattle to Inverness flights

Portland to Aberdeen flights

Seattle to Bristol flights

Portland to Leeds flights

Seattle to Newcastle upon Tyne flights

Portland to Bristol flights

Seattle to Leeds flights

Seattle to Belfast City flights

Spokane to Manchester flights

Portland to Belfast Intl flights

Portland to Belfast City flights

Seattle to Liverpool flights

Seattle to Aberdeen flights

Portland to Southend flights

Spokane to Southampton flights

Bellingham to Gatwick flights

Direct flights to United Kingdom

Fly with Cheapflights

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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.

Cheap flights from Seattle to Northern Ireland from £570

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/12. 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

Keep the following information in mind while searching for Seattle to Northern Ireland flight deals. Data was last updated 2 July 2025.

Round-trip from

Popular in

Cheapest in

Average price

Find flight deals from Seattle to Northern Ireland

Cheapest flights from Seattle to Northern IrelandExplore 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 2 July 2025.

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 2 July 2025.

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

Reviews of airlines servicing Northern Ireland

Read through reviews of airlines operating flights from Seattle to Northern Ireland, such as Delta, KLM, andBritish Airways. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

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?

What is the cheapest month to book a flight 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?

100% Free

Book with Flexibility

Travel Smart

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 2 July 2025.