PlainFlights

Route · FLL → ISP · 2020–2025 BTS data

Fort Lauderdale to Islip

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), FLL to ISP (Fort Lauderdale to Islip) ranks #4345 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

74.4%
On-time
-4.6 pts
vs US avg
71 min
Delay when late
1,202
Flights
#4345 of 4927
Corpus placement

Cancelled

2.8%

Best Month

May 2025 81%

Worst Month

Mar 2022 45%

Distance

1,092 mi

Carriers

8

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 46 17 1 0 F9,B6
Nov 2025 33 10 0 0 B6
Aug 2025 31 1 0 0 B6
Jul 2025 31 5 0 0 B6
May 2025 52 10 0 0 B6,F9
Apr 2025 47 5 0 0 F9,B6
Mar 2025 35 7 1 1 B6,WN,F9
Feb 2025 35 6 0 0 B6,WN,F9
Dec 2024 32 4 2 0 B6,F9
Aug 2024 36 17 3 0 F9
Jul 2024 31 13 1 0 F9
Jun 2024 30 9 1 0 F9
May 2024 31 6 1 0 F9
Apr 2024 30 3 1 1 F9
Mar 2024 33 14 0 1 F9,WN
Feb 2024 30 8 0 0 F9,WN
Dec 2023 38 18 3 0 F9,WN
Aug 2023 31 15 0 0 F9
Jul 2023 31 15 0 0 F9
Jun 2023 30 9 2 0 F9
May 2022 31 4 1 0 F9
Mar 2022 60 33 2 0 F9,WN
Feb 2022 40 13 0 0 F9,WN
Jan 2022 31 5 5 0 WN

FLL–ISP seasonal on-time pattern

Best: April (90.0%) · weakest: July (64.5%)

60%70%80%90%100% JanFebMarAprMayJunJulAugNovDec 65.3%

Strongest calendar month

April

90.0% on-time · ~35 flights/mo

Busiest calendar month

January

~49 flights/mo avg

Weakest calendar month

July

64.5% on-time · ~31 flights/mo

Cancellation Rate

2.8%

24 of 855 flights

Diversion Rate

0.4%

3 of 855 flights

Origin-hub reliability standing

Softer reliability from FLL

Among 62 routes leaving FLL, only 29 (including this one) clear below 75% on-time, while 1 stay ≥85% and 32 sit mid-band. Travelers comparing FLL options should weigh this 74.4% print against those peers · fleet on-time rank #4557 of 4927.

What the Data Says About FLL to ISP

On-time performance on the FLL to ISP pairing (Fort Lauderdale to Islip) trails a chunk of the network: 74.4% of 1,202 tracked flights arrived on schedule, with a 71.0-minute average delay on the ones that ran late. The route spans about 1,092 miles across 8 carriers. Cancellations over the trailing 24 months hit 2.8% (24 of 855 flights), with 0.4% diverted.

The monthly split is wide on this route: May 2025 posted the strongest performance at 81% on-time, while Mar 2022 came in at just 45% - a 36-point swing worth factoring into travel timing.

On the multi-year calendar, FLL–ISP peaks in April at 90.0% on-time while January carries the heaviest traffic (~49 flights per month) ; the softest month is July at 64.5%, a 25.5-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does FLL to ISP rank among US routes by traffic?
According to PlainFlights' route traffic ranking, FLL to ISP ranks #4345 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from FLL to ISP?
Flights from Fort Lauderdale to Islip have a 74.4% on-time rate based on 1,202 flights. The average delay is 71.0 minutes. The best recent month was May 2025 with 81% on-time.
What is the cancellation rate for FLL to ISP?
Over the last 24 months, 2.8% of flights on this route were cancelled (24 of 855 flights) and 0.4% were diverted.
How far is the flight from FLL to ISP?
The flight distance from Fort Lauderdale (FLL) to Islip (ISP) is approximately 1,092 miles. This route is served by 8 carriers.
When is the best time to fly from FLL to ISP?
The best recent month for on-time performance was May 2025 (81% on-time). The worst was Mar 2022 (45% on-time). Consider booking during months with historically better performance.

Airports on this route

Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Using FLL–ISP data

FLL–ISP sits 4.6 pts below the national 79% average; check the seasonal chart and airport profiles before treating the headline as typical.

  • Compare FLL and ISP airport profiles: delay causes and top routes differ even on the same corridor. FLL airport
  • If your dates flex, April (90.0% on-time) beats July (64.5%) on this corridor. Seasonal chart
  • 4 other routes post a similar 74.4% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.