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Cheap Flights from Seattle (SEA) to Belfast (BFS)

Popular airlines from Seattle-Tacoma International Airport (SEA) to Belfast International Airport (BFS)

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Find the cheapest month to fly from Seattle (SEA) to Belfast (BFS)

January is typically the cheapest month to fly

From £447 - £900 per traveller.

Frequently asked questions

How much does a flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) cost?
You can find one-way and return flights from SEA to BFS with Expedia. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see our cheapest fares first, and use the Price Tracking tool to receive alerts when SEA to BFS ticket fares go up or down.
What is the cheapest month to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
The cheapest months to fly from SEA to BFS are typically during off-peak season when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you are able to. Use the calendar view in your search to see which months have low fares on this route.
Which airlines fly direct from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
Enter SEA to BFS and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
What is the cheapest airline that flies from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
Aer Lingus is one of the cheapest airlines offering connecting return flights from Seattle - Tacoma Intl. (SEA) to Belfast Intl. (BFS), with tickets starting from around £1002 for flights that can be booked for departure within the next year. These flights typically include a layover in Dublin (DUB). Prices are per adult for economy/coach class. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.
How do I find cheap flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
To find a cheap flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
What is the earliest flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
The earliest flight from Seattle - Tacoma Intl. (SEA) to Belfast Intl. (BFS) typically departs around 5:15 AM. This flight is operated by American Airlines and British Airways. This is a seasonal service, active only in December. An early departure like this can help you make the most of your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
You'll find the most flights from Seattle - Tacoma Intl. (SEA) to Belfast Intl. (BFS) on a Thursday, with around 48 flights available. This gives you a good selection of options for your travel plans. Major airlines on this route include Delta, American Airlines, and British Airways. Compared to other days, Thursday has notably more flight options, making it a great day to consider for your journey.
What are the most popular departure times for flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
The most popular departure times for flights from Seattle - Tacoma Intl. (SEA) to Belfast Intl. (BFS) are between 12pm and 3pm. Many major carriers, including British Airways, American Airlines and Delta, offer flights during this window. Many travellers prefer this time as it allows for a morning in Seattle before your flight, and you'll arrive in Belfast at a reasonable hour.
Can you fly business or first class from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
You can fly business class between SEA and BFS. Airlines that offer business class service on this route include:

  • Air France
  • British Airways
  • Alaska Airlines
  • Delta
  • Finnair
  • American Airlines

How do I earn miles on a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) flight with Expedia?
It's easy to earn miles on a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Belfast (BFS) from Seattle, WA (SEA)?
If you're planning to travel to Belfast from Seattle - Tacoma Intl. (SEA), you can fly directly into Belfast Intl. (BFS). Some flights may connect through major hubs like Dallas-Fort Worth Intl. (DFW), Heathrow (LHR), or O'Hare Intl. (ORD) before reaching Belfast. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) at the last minute?
Typically, booking a last minute flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) flight and hotel package?
Securing a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.)?
If you booked your Seattle, WA (SEA-Seattle - Tacoma Intl.) to Belfast (BFS-Belfast Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Belfast Intl.
Distance
7141 km

Book with confidence

Compare flights from Seattle to Belfast easily and book with confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from Seattle to Belfast. Operating between them flights per day, airlines cover the route. And fly direct, getting you to Belfast Intl. in just hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Seattle - Tacoma Intl. to Belfast Intl..  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Seattle - Tacoma Intl. (SEA) to Belfast Intl. (BFS)

The easiest way to view the best deals on flights from Seattle to Belfast today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Seattle - Tacoma Intl. to Belfast Intl. start at just and range up to .  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near Seattle and Belfast
  • booking your flight during , the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your Seattle to Belfast flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Seattle - Tacoma Intl. to Belfast Intl. for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

Compare flights from Seattle to Belfast easily and book with confidence

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