$463 Cheap Aer Lingus flights Seattle (SEA) to Southampton (SOU)

You can find affordable round-trip Aer Lingus flights from $603 from SEA to SOU by organizing your results from "Price (lowest to highest)" on Expedia. Or look for options from $463 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.

Landing the best Aer Lingus deals from SEA to SOU often comes down to booking at the right time. You can save 17% on international flights when you book 18 to 29 days before takeoff instead of four to five months ahead. Better yet, you can pocket 17% on average by buying your fare on a Sunday rather than a Friday, which is usually the most expensive day to book.* It's a good idea to start checking out flights about one month before you plan to travel.*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.

Browse Aer Lingus's earliest flights from SEA to SOU by using the "Early Morning" and "Morning" filters. Not only will you arrive sooner, early departures also have a 20% less chance of being canceled.**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.

Aer Lingus makes flying from SEA to SOU more enjoyable with a 4-star airline rating and a rewarding loyalty program. You even have the chance to collect points with Aer Lingus AerClub. Be sure to sign up to our free One Key™ rewards program to earn OneKeyCash™*, which can be redeemed on future travel.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.