Cheap flights from Seattle to Belfast from $791
This is the cheapest round-trip flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Belfast departing on 10/4. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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How to get the cheapest flight ticket from Seattle to Belfast Intl Airport
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 day to depart on your flight to Belfast Intl Airport?
The cheapest day to depart on your flight to Belfast Intl Airport is on a Tuesday when prices can be found for as low as $724. This is often the case because there is less demand to fly during this day of the week. When flying out on a Wednesday, the most expensive travel day of the week, you can expect to see flight prices from Seattle to Belfast Intl Airport for around $1,208.
What is the cheapest time of day to depart on your flight to Belfast Intl Airport?
At noon is the cheapest time of day to fly from Seattle to Belfast Intl Airport when you can find flight prices for as low as $794. Flying to Belfast Intl Airport at noon is an ideal time because this is during off-peak travel hours. In contrast, the most expensive time of day to depart to Belfast Intl Airport is in the afternoon when prices are around $1,000.
When to book flights from Seattle to Belfast Intl Airport
Cheap Seattle to Belfast Intl Airport (SEA to BFS) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Seattle to Belfast Intl Airport
How far is Seattle/Tacoma Intl to Belfast Intl by plane?
Belfast Intl is 4452.2 mi away from Seattle/Tacoma Intl. By plane, this route typically takes 16h 50m.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Belfast Intl Airport?
Prices for flights from Seattle/Tacoma Intl Airport to Belfast Intl Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Belfast Intl Airport?
As of June 2025, there is 1 operator available to choose from for flights from Seattle/Tacoma Intl Airport to Belfast Intl Airport.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Belfast Intl Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Belfast Intl Airport.
What documentation or ID do you need to fly to Belfast Intl Airport?
The travel and health documents required for your trip to Belfast 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 Belfast Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular airline from Seattle to Belfast Intl Airport?
momondo data reveals that the most frequently booked airline on the route from Seattle to Belfast Intl Airport is British Airways, representing 100% of all bookings.
Best airlines flying from Seattle to Belfast Intl Airport
Compare and see reviews for airlines that fly from Seattle to Belfast Intl Airport with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $519 | Free Cancellation | Rating 6.6 7,008 reviews |
Traveling to a place near Belfast?
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Why should I use momondo to find a flight deal from Seattle to Belfast?
It is quick and easy to find Seattle to Belfast flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Belfast that suits you.
Can I find flights from Seattle to Belfast with flexible booking policies on momondo?
Flights from Seattle to Belfast with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from Seattle to Belfast?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Seattle to Belfast.
I’m not ready to book a flight from Seattle to Belfast right now. Can momondo alert me if prices change?
Yes. momondo can track prices for Seattle to Belfast flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.