Fort Lauderdale to Islip

What the Data Says About FLL to ISP

The Fort Lauderdale to Islip corridor (FLL → ISP) covers roughly 1,092 miles and is served by 8 carriers, based on Bureau of Transportation Statistics reporting. Across 1,202 flights in the dataset, this route posts a 74.4% on-time rate with an average delay of 71.0 minutes when flights run late. Over the most recent 24 months of BTS data, 855 flights were recorded on this pairing — 24 cancelled (2.8%) and 3 diverted (0.4%). Those baseline metrics tell you what to expect before you book.

Having 8 carriers on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 1,202 total flights analyzed, the 74.4% on-time figure is statistically meaningful rather than a small-sample fluke. The 71.0-minute average delay applies only to flights that actually ran late, so it is not the average wait across all departures — the majority of flights on this route depart on time under the BTS definition of a delay (15+ minutes past schedule).

Looking at recent months, May 2025 posted the best performance on this corridor at 81% on-time, while Mar 2022 came in at 45% on-time — a 36-point gap between best and worst recent month. For travelers evaluating the FLL to ISP route, the combination of a 74.4% on-time rate, 71.0-minute average delay, 2.8% recent cancellation rate, and 8 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.