70% of flights from Islip to West Palm Beach arrived on time over the past 12 months. That is worse than the typical U.S. route. The 6 a.m. departures ran on time 82% of the time; the 2 p.m. ones 53%. Most reliable airline: JetBlue (71%). 11% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for ISP → PBI: when a flight was late, it was under 45 minutes late 56% of the time. About 1 in 12 flights landed an hour or more late, and 1 in 52 three hours or more; 2.3% were cancelled outright.
- On time or early70%
- 15–30 min late10%
- 30–60 min late8.3%
- 1–2 hours late4.6%
- 2–3 hours late1.9%
- 3+ hours late1.9%
- Diverted0.4%
- Cancelled2.3%
Share of all 1,133 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| JetBlue | 540 | 71% | 2.6% | −5 min | 10.2% | +95 min | JetBlue |
| Southwest Airlines | 524 | 69% | 1.7% | +3 min | 6.1% | +50 min | Southwest Airlines |
| Frontier Airlines | 69 | — | — | — | — | — | Frontier Airlines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at ISP). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | JetBlue |
|---|---|
| 3 p.m. | 64% |
Last flight of the day
On ISP → PBI, each airline's last flight of the day was cancelled 2.6% of the time, against 3.0% for its earlier flights, about the same. It arrived 3+ hours late 2.1% of the time (earlier flights: 1.8%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| JetBlue | 2:40 p.m. | 3.4% | 1.9% | 3.4% | first flight 7:00 a.m. |
| Southwest Airlines | 11:10 a.m. | 1.7% | 2.2% | 2.6% | first flight 11:10 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
By month
Each calendar month pooled over 2023–2026. Best: November (84%). Worst: December (62%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 163 | 65% | 5.5% |
| Tuesday | 161 | 71% | 1.9% |
| Wednesday | 159 | 72% | 0.0% |
| Thursday | 163 | 73% | 0.0% |
| Friday | 163 | 77% | 0.0% |
| Saturday | 155 | 69% | 1.9% |
| Sunday | 169 | 64% | 6.5% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 16 · airline 7 · air traffic/airport 3
Month by month
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| B6 545 | 1:55 p.m. | 326 | 66% | 2.1% | −2 min | JetBlue |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Feb 23, 2026 | 5 | 0% | 5 |
| Jan 18, 2026 | 5 | 0% | 0 |
| Jan 25, 2026 | 4 | 0% | 3 |
| Dec 7, 2025 | 4 | 0% | 0 |
| Dec 14, 2025 | 4 | 0% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Islip or West Palm Beach. EWR → PBI has been 5 points more reliable.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| ISP → PBI (this route) | 1,133 | 70% | 2.3% |
| EWR → PBI Newark to President Donald J. Trump | 3,395 | 75% | 2.8% |
| EWR → FLL Newark to Fort Lauderdale | 4,671 | 72% | 4.0% |
| JFK → PBI New York JFK to President Donald J. Trump | 2,050 | 71% | 4.6% |
| HPN → PBI Westchester to President Donald J. Trump | 1,574 | 70% | 3.0% |
| HPN → FLL Westchester to Fort Lauderdale | 880 | 69% | 2.5% |
| JFK → FLL New York JFK to Fort Lauderdale | 3,907 | 68% | 4.8% |
Questions
How often are flights from ISP to PBI on time?
70% of 1,133 scheduled flights from Islip, NY to West Palm Beach/Palm Beach, FL arrived within 15 minutes of schedule between September 2025 and August 2026. 2.3% were cancelled.
What is the best time of day to fly ISP to PBI?
Flights scheduled to leave at 6 a.m. were the most reliable (82% on time). The 2 p.m. departures were the least (53%).
Which airline is most on time from ISP to PBI?
JetBlue: 71% of its 540 flights on the route arrived on time. Southwest Airlines: 69%.
What month has the most delays from ISP to PBI?
December (62% on time). The best month is November (84%), over 2023–2026.
Is the last flight of the day from ISP to PBI more likely to be cancelled?
Not much. Each airline's last ISP–PBI flight of the day was cancelled 2.6% of the time over the past year, against 3.0% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- PBI → ISP (return)
- Long Island MacArthur (ISP) delays by hour
- Flights into President Donald J. Trump (PBI)
- JetBlue on-time record
- Southwest Airlines on-time record
- Frontier Airlines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.