$340 Cheap United flights Boston (BOS) to Reykjavik (KEF)

Grab cheap return United Airlines flights from $426 from BOS to KEF by organizing your results from "Price (lowest to highest)" on Expedia. Or look for deals from $340 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.

Scoring the best United Airlines deals from BOS to KEF 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. What's more, you can pocket 17% on average by buying your tickets on a Sunday compared to a Friday, which is often the most expensive day to book.* It's a good idea to start checking out flights about one month before your travel dates.*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.

To find the earliest departures from BOS to KEF with United Airlines, filter your results by "Early Morning" and "Morning." Booking an early flight usually means you'll experience fewer 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.

With a rewarding loyalty program, United Airlines is a favorite of many passengers heading from BOS to KEF. Plus, as 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.