$131 Cheap Frontier Airlines flights Houston (IAH) to Islip (ISP)

Apply the “Price (lowest to highest)” filter on Expedia to find cheap Frontier Airlines return flights from $250 from IAH to ISP. Affordable one-way tickets from $131 are available too.**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.

Search for one-way or return flights to Islip in January or February. You could find an affordable fare with Frontier Airlines during these off-season months.

Look for cheap Frontier Airlines flights from George Bush Intercontinental Airport (IAH) to MacArthur Airport (ISP) one to three months before your departure day. 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 type and journey, the best day of the week to book a domestic flight is generally 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 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 out if there’s a direct route from IAH to ISP with Frontier Airlines or any other carriers, select the “Nonstop” filter when looking for tickets.

Sort your results by “Early Morning” and “Morning” to browse the earliest departures from IAH to ISP. Leaving early means you’re 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.

MacArthur Airport (ISP) is the main Islip hub for Frontier Airlines flights from George Bush Intercontinental Airport (IAH).

Travel from IAH to ISP with Frontier Airlines and enjoy a range of perks including a rewarding loyalty program. When booking through Expedia as a Frontier Miles and One Key™ member, you can also earn OneKeyCash™* to spend on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.

Depending on the type of fare you purchased, a fee generally applies if you modify or cancel your flight more than 24 hours after it’s been confirmed. To find flexible plane tickets, select our “Changes included” and “No cancel fee” boxes when searching for flights. To learn more about modifying or canceling your reservation, head to “Trips,” select your flight and tick “Manage Booking.”