West Palm Beach/Palm Beach to Islip

What the Data Says About PBI to ISP

The West Palm Beach/Palm Beach to Islip corridor (PBI → ISP) covers roughly 1,052 miles and is served by 8 carriers, based on Bureau of Transportation Statistics reporting. Across 4,599 flights in the dataset, this route posts a 76.2% on-time rate with an average delay of 71.1 minutes when flights run late. Over the most recent 24 months of BTS data, 2,256 flights were recorded on this pairing — 22 cancelled (1.0%) and 8 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 4,599 total flights analyzed, the 76.2% on-time figure is statistically meaningful rather than a small-sample fluke. The 71.1-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, Nov 2024 posted the best performance on this corridor at 93% on-time, while Jun 2025 came in at 64% on-time — a 29-point gap between best and worst recent month. For travelers evaluating the PBI to ISP route, the combination of a 76.2% on-time rate, 71.1-minute average delay, 1.0% recent cancellation rate, and 8 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.