$154 Cheap Frontier Airlines flights San Antonio (SAT) to Islip (ISP)

Use the “Price (lowest to highest)” filter on Expedia to search for cheap Frontier Airlines round-trip flights from $320 from SAT to ISP. Affordable one-way tickets from $154 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.

January is one of the most affordable months to fly to Islip with Frontier Airlines. You could also find excellent prices on one-way and return tickets in February.

Start searching one to three months before your departure to find cheap fares on Frontier Airlines flights from San Antonio Intl. Airport (SAT) to MacArthur Airport (ISP). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it’s 6% cheaper on average than a Monday, the most expensive day to book.* Nail your timing, and you can enjoy significant savings on domestic flights.*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 SAT to ISP with Frontier Airlines or other carriers, select the “Nonstop” filter when searching for flights.

Browse Frontier Airlines’s earliest flights from SAT to ISP by selecting our “Early Morning” and “Morning” filters. Not only will you get to where you’re going 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.

Frontier Airlines flights from San Antonio Intl. Airport (SAT) to Islip arrive at MacArthur Airport (ISP). This is the main gateway to this city.

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

Changes are often free within 24 hours of booking, but your airline may add a charge after that time. For more details about modifying your reservation, head to your “Trips,” select your flight and click on “Manage Booking.” If you want the freedom to update your itinerary without extra charges, tick the “Changes included” and “No cancel fee” filters when planning your next trip.