Long Island MacArthur in May 2025

74.4%departed on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.

In May 2025, reporting carriers scheduled 536 domestic departures from Long Island MacArthur (ISP). 74.4% left less than 15 minutes late and 71.6% reached their destination on time; 1.7% were cancelled.

Nationally that month, 76.7% of flights departed on time and 75.4% arrived on time, so ISP departures were 2.3 points below the national departure figure.

A year earlier, in May 2024, the airport had 417 departures with 73.9% leaving on time: a change of +0.5 points, with flights up 29%.

Flights arriving at ISP that month were on time 73.7% of the time (536 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 46%, air carrier 27% and national aviation system 25%.

On time 71.6%
Arrived 15+ minutes late 25.9%
Cancelled 1.7%
Diverted 0.7%

Every scheduled departure from ISP in May 2025, judged by arrival at the destination.

May 2025 against a year earlier, the airport's year and the nation

Measure	May 2025	May 2024	ISP, 12 months to Jul 2026	All reported flights, May 2025
Departed on time	74.4%	73.9%	73.7%	76.7%
Arrived on time	71.6%	79.6%	73.6%	75.4%
Cancelled	1.7%	1.9%	2.1%	1.0%
Average departure delay (late minutes only)	20.2 min	17.3 min	18.8 min	17.5 min
Scheduled departures a day	18	14	14	20,188
Scheduled departures	536	417	4,966	605,648

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	313	58%	76.0%	10.8 min	0.0%
F9 Frontier Airlines	124	23%	67.7%	17.9 min	2.4%
B6 JetBlue Airways	99	18%	62.6%	16.5 min	6.1%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ISP–MCO	Islip to Orlando	128	67.2%	15.3 min	0.0%
ISP–BWI	Islip to Baltimore	114	76.3%	12.4 min	0.0%
ISP–PBI	Islip to West Palm Beach/Palm Beach	113	75.2%	3.1 min	0.9%
ISP–TPA	Islip to Tampa	65	69.2%	20.7 min	3.1%
ISP–FLL	Islip to Fort Lauderdale	52	71.2%	23.3 min	0.0%
ISP–MIA	Islip to Miami	31	83.9%	12.9 min	0.0%
ISP–MYR	Islip to Myrtle Beach	18	66.7%	20.4 min	0.0%
ISP–RSW	Islip to Fort Myers	9	66.7%	10.6 min	0.0%
ISP–BOS	Islip to Boston	6	0.0%	—	100.0%

By scheduled departure hour

100

On-time share:under 62%6270768288% and over

Share of departures that left less than 15 minutes late, by scheduled hour (local time), May 2025.

Delay causes

BTS cause category	Share of delay minutes	National, May 2025	Minutes
Air carrier	27.4%	29.3%	2,903
Late-arriving aircraft	45.8%	37.8%	4,848
National Aviation System	24.5%	25.9%	2,594
Extreme weather	2.2%	6.9%	237
Security	0.0%	0.1%	0

10,582 delay minutes on 139 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Questions and answers

How many flights left ISP on time in May 2025?

74.4% of 536 scheduled domestic departures left less than 15 minutes late, and 71.6% reached their destination on time. The national figures that month were 76.7% and 75.4%.

How does that compare with a year earlier?

In May 2024, 73.9% of 417 departures left on time and 1.9% were cancelled, against 74.4% and 1.7% in May 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for May 2025; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for ISP · methodology · corrections.