$89 Cheap Frontier Airlines flights Fort Lauderdale (FLL) to Islip (ISP)

You can find budget-friendly return Frontier Airlines flights from $193 from FLL to ISP by sorting your results from "Price (lowest to highest)" on Expedia. Or search for bargains from $89 for a one-way trip.**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.

Look for cheap Frontier Airlines flights from Fort Lauderdale - Hollywood Intl. Airport (FLL) to MacArthur Airport (ISP) one to three months prior to your day of departure. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. Regardless of fare class and journey, the best day to book a domestic flight is usually Sunday and the most expensive tends to be Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**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 FLL to ISP with Frontier Airlines, sort your results by "Morning" and "Early 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.

A rewarding loyalty program and the chance to rack up points through Frontier Miles are the start of the reasons to travel from FLL to ISP with Frontier Airlines. Plus, when you sign up to Expedia's free One Key™ program, you can receive OneKeyCash™* alongside any airline loyalty program earnings. It's yours to spend on future bookings.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.