Cheap United flights Athens (ATH) to Nantucket (ACK)

Apply the "Price (lowest to highest)" filter on Expedia to find cheap United Airlines round-trip flights from ATH to ACK. Affordable one-way options are available as well.**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.

Scoring the best United Airlines deals from ATH to ACK often comes down to booking at the right moment. You can save 17% on international flights when you book 18 to 29 days before takeoff instead of four to five months ahead. To top it off, you can pocket 17% on average by buying your tickets on a Sunday rather than a Friday, which is usually the most expensive day to book.* It's a good idea to start searching for flights about one month before you want 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.

Filter your results by "Early Morning" and "Morning" to browse the earliest flights from ATH to ACK. Setting off early means you're 20% less likely to experience cancellations.**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.

Offering a rewarding loyalty program, United Airlines is a favorite of many travelers departing from ATH to ACK. Plus, if you're a United Mileage Plus and One Key™ member booking through Expedia, you can earn OneKeyCash™* on eligible flights on top of your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.