PlainFlights

Route · ISP → FLL · 2020–2025 BTS data

Islip to Fort Lauderdale

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), ISP to FLL (Islip to Fort Lauderdale) ranks #4393 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

78.1%
On-time
-0.9 pts
vs US avg
76 min
Delay when late
1,139
Flights
#4393 of 4927
Corpus placement

Cancelled

2.3%

Best Month

May 2025 71%

Worst Month

Mar 2022 68%

Distance

1,092 mi

Carriers

8

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 45 20 1 0 F9,B6
Nov 2025 33 14 0 0 B6
Aug 2025 31 8 0 0 B6
Jul 2025 31 9 0 1 B6
May 2025 52 15 0 0 B6,F9
Apr 2025 47 7 0 0 F9,B6
Mar 2025 35 9 1 0 B6,WN,F9
Feb 2025 35 11 0 0 B6,WN,F9
Dec 2024 32 9 0 0 B6,F9
Aug 2024 36 12 1 0 F9
Jul 2024 31 7 1 0 F9
Jun 2024 30 4 0 0 F9
May 2024 31 5 1 0 F9
Apr 2024 30 3 1 0 F9
Mar 2024 33 10 0 0 F9,WN
Feb 2024 30 4 0 1 F9,WN
Dec 2023 38 14 3 0 F9,WN
Aug 2023 31 4 1 0 F9
Jul 2023 31 5 2 0 F9
Jun 2023 30 3 2 0 F9
May 2022 31 9 1 0 F9
Mar 2022 60 19 5 0 F9,WN
Feb 2022 40 10 0 1 F9,WN
May 2021 31 10 0 0 WN

ISP–FLL seasonal on-time pattern

Best: January (91.0%) · weakest: November (57.6%)

50%60%70%80%90%100% JanFebMarAprMayJunJulAugNovDec 62.6%

Strongest calendar month

January

91.0% on-time · ~67 flights/mo

Busiest calendar month

January

~67 flights/mo avg

Weakest calendar month

November

57.6% on-time · ~33 flights/mo

Cancellation Rate

2.3%

20 of 854 flights

Diversion Rate

0.4%

3 of 854 flights

Explore origin & destination

On-time and delay data for the airports this route connects.

ISP - Islip

Full on-time, delay-cause, and seasonal performance for Islip, NY.

ISP on-time profile

FLL - Fort Lauderdale

Full on-time, delay-cause, and seasonal performance for Fort Lauderdale, FL.

FLL on-time profile

Compare the two airports

See ISP and FLL side by side on delays, cancellations, and reliability.

Compare ISP vs FLL

Origin-hub reliability standing

Mid-pack among ISP departures

From ISP, this corridor sits with 3 other 75–85% on-time routes out of 5 tracked departures, not the hub's reliability leaders (1 at ≥85%) and not the softest ( 1 below 75%). Destination: Fort Lauderdale · fleet on-time rank #3814 of 4927.

What the Data Says About ISP to FLL

The Islip to Fort Lauderdale corridor (ISP to FLL) posts a 78.1% on-time rate on the lower edge of the average band, based on 1,139 tracked flights. Late flights run 75.8 minutes behind on average. 8 carriers cover the 1,092-mile route; over the last 24 months, 20 of 854 flights were cancelled (2.3%) and 0.4% diverted.

Monthly on-time rates stay fairly consistent on this route, ranging from 68% in Mar 2022 to 71% in May 2025 - only a 3-point spread.

On the multi-year calendar, ISP–FLL peaks in January at 91.0% on-time ; the softest month is November at 57.6%, a 33.4-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does ISP to FLL rank among US routes by traffic? ▼
According to PlainFlights' route traffic ranking, ISP to FLL ranks #4393 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 ISP to FLL? ▼
Flights from Islip to Fort Lauderdale have a 78.1% on-time rate based on 1,139 flights. The average delay is 75.8 minutes. The best recent month was May 2025 with 71% on-time.
What is the cancellation rate for ISP to FLL? ▼
Over the last 24 months, 2.3% of flights on this route were cancelled (20 of 854 flights) and 0.4% were diverted.
How far is the flight from ISP to FLL? ▼
The flight distance from Islip (ISP) to Fort Lauderdale (FLL) is approximately 1,092 miles. This route is served by 8 carriers.
When is the best time to fly from ISP to FLL? ▼
The best recent month for on-time performance was May 2025 (71% on-time). The worst was Mar 2022 (68% on-time). Consider booking during months with historically better performance.

Airports on this route

ISP Airport

Islip
FLL Airport

Fort Lauderdale
Data source

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

Read our methodology - how this data is sourced, computed, and verified.

Using ISP–FLL data

ISP–FLL is mid-pack at 78.1% on-time; month and carrier mix move more than the corridor headline.

  • Compare ISP and FLL airport profiles: delay causes and top routes differ even on the same corridor. ISP airport
  • If your dates flex, January (91.0% on-time) beats November (57.6%) on this corridor. Seasonal chart
  • 4 other routes post a similar 78.1% 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.