$637 Cheap British Airways flights Seattle (SEA) to Londonderry (LDY)

View $637 flight on Mon, Sep 29, 2025Opens in a new window

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$637 Cheap British Airways flights Seattle (SEA) to Londonderry (LDY)

Prices were available within the past 7 days and start at $637 for one-way flights and $895 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

British Airways
Mon, Dec 1 - Fri, Dec 12
SEA
Seattle
LDY
Londonderry
$895 Roundtrip, found 3 days ago
$895
Roundtrip
found 3 days ago
Select British Airways flight, departing Mon, Dec 1 from Seattle to Londonderry, returning Fri, Dec 12, priced at $895 found 3 days ago
British Airways
Mon, Sep 29 - Mon, Oct 6
SEA
Seattle
LDY
Londonderry
$1,006 Roundtrip, found 4 days ago
$1,006
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Sep 29 from Seattle to Londonderry, returning Mon, Oct 6, priced at $1,006 found 4 days ago
British Airways
Mon, Sep 29 - Mon, Oct 6
SEA
Seattle
LDY
Londonderry
$1,028 Roundtrip, found 4 days ago
$1,028
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Sep 29 from Seattle to Londonderry, returning Mon, Oct 6, priced at $1,028 found 4 days ago
British Airways
Mon, Sep 29 - Mon, Oct 6
SEA
Seattle
LDY
Londonderry
$1,043 Roundtrip, found 4 days ago
$1,043
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Sep 29 from Seattle to Londonderry, returning Mon, Oct 6, priced at $1,043 found 4 days ago
British Airways
Mon, Sep 29 - Mon, Oct 6
SEA
Seattle
LDY
Londonderry
$1,044 Roundtrip, found 4 days ago
$1,044
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Sep 29 from Seattle to Londonderry, returning Mon, Oct 6, priced at $1,044 found 4 days ago
British Airways
Mon, Sep 29 - Mon, Oct 6
SEA
Seattle
LDY
Londonderry
$1,045 Roundtrip, found 4 days ago
$1,045
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Sep 29 from Seattle to Londonderry, returning Mon, Oct 6, priced at $1,045 found 4 days ago
Flights from Seattle (SEA) to Londonderry (LDY)
Origin airport
Seattle - Tacoma Intl.
Destination airport
City of Derry
Distance
4418 mi

Frequently asked questions

How much is a British Airways flight from Seattle - Tacoma Intl. Airport (SEA) to City of Derry Airport (LDY)?
You'll find cheap round-trip British Airways flights from $895 from SEA to LDY by filtering your results from "Price (lowest to highest)" on Expedia. Or search for options from $637 for a one-way journey.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from SEA to LDY with British Airways?
February is one of the most affordable months to jet off to Londonderry with British Airways. You could also find great deals on one-way and return fares in January.
What is the cheapest time to book flights from Seattle - Tacoma Intl. Airport (SEA) to City of Derry Airport (LDY) with British Airways?
Search for British Airways flights from SEA to LDY about one month before you want to go. The cheapest time to book an international flight is usually 18 to 29 days ahead of your travel date when you can save 17% versus booking four to five months in advance. Regardless of itinerary and fare class, the best day of the week to book international airfare is usually Sunday. Friday is often the most expensive. Passengers booking on a Sunday can save 17% on average compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does British Airways fly nonstop from Seattle - Tacoma Intl. Airport (SEA) to City of Derry Airport (LDY)?
Fill in your dates, hit search and tick the "Nonstop" filter on Expedia to find any direct flights from SEA to LDY with British Airways or other carriers.
What is the earliest British Airways flight from SEA to LDY?
To find the earliest departures from SEA to LDY with British Airways, filter your search by "Early Morning" and "Morning." Booking an early flight usually means cancellations are less likely.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does British Airways fly into in Londonderry?
City of Derry Airport (LDY) is the primary Londonderry gateway for British Airways flights from Seattle - Tacoma Intl. Airport (SEA).
What kind of luggage can I take on a British Airways flight from Seattle - Tacoma Intl. Airport (SEA) to City of Derry Airport (LDY)?
British Airways allows travelers to bring 1 checked-in bag weighing up to 50 lb with dimensions not exceeding 29 inches x 15 inches x 16 inches on standard economy flights from SEA to LDY. Additionally, you can take 2 cabin bags in the cabin. This hand luggage must not exceed 19 inches x 9 inches x 17 inches and weigh no more than 50 lb. Baggage allowances can differ based on your fare type and cabin class, so double-check your booking or British Airways's website to avoid any extra fees at the airport.
Why fly with British Airways from SEA to LDY?
Jetting off from SEA to LDY with British Airways comes with a range of perks, including an excellent in-flight experience and a 4-star airline rating. Plus, when booking through Expedia, One Key™ members can collect OneKeyCash™* to redeem on select future travel purchases. That's in addition to the British Airways Executive Club points you can earn with British Airways.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my British Airways flight from Seattle - Tacoma Intl. Airport (SEA) to City of Derry Airport (LDY)?
Depending on the type of fare you purchased, a fee will generally apply if you modify or cancel your booking more than 24 hours after it has been confirmed. To secure flexible fares, select our "Changes included" and "No cancel fee" boxes when you look for flights. To learn more about canceling or modifying your reservation, visit "Trips," select your flight and tick "Manage Booking."

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