Long Island MacArthur in December 2025

62.2%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 December 2025, reporting carriers scheduled 458 domestic departures from Long Island MacArthur (ISP). 62.2% left less than 15 minutes late and 62.9% reached their destination on time; 2.4% were cancelled.

Nationally that month, 72.0% of flights departed on time and 71.9% arrived on time, so ISP departures were 9.8 points below the national departure figure.

A year earlier, in December 2024, the airport had 432 departures with 68.1% leaving on time: a change of −5.9 points, with flights up 6%.

Flights arriving at ISP that month were on time 65.9% of the time (460 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 44%, air carrier 34% and national aviation system 21%.

On time 62.9%
Arrived 15+ minutes late 34.5%
Cancelled 2.4%
Diverted 0.2%

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

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

Measure	Dec 2025	Dec 2024	ISP, 12 months to Jul 2026	All reported flights, Dec 2025
Departed on time	62.2%	68.1%	73.7%	72.0%
Arrived on time	62.9%	71.1%	73.6%	71.9%
Cancelled	2.4%	0.7%	2.1%	1.5%
Average departure delay (late minutes only)	29.2 min	26.3 min	18.8 min	21.2 min
Scheduled departures a day	15	14	14	19,410
Scheduled departures	458	432	4,966	582,304

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	234	51%	65.0%	18.5 min	0.4%
B6 JetBlue Airways	122	27%	60.7%	40.3 min	0.8%
F9 Frontier Airlines	102	22%	60.8%	20.2 min	8.8%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ISP–PBI	Islip to West Palm Beach/Palm Beach	133	56.4%	25.4 min	1.5%
ISP–MCO	Islip to Orlando	132	64.4%	19.3 min	3.0%
ISP–BWI	Islip to Baltimore	93	77.4%	13.3 min	0.0%
ISP–TPA	Islip to Tampa	49	61.2%	30.4 min	8.2%
ISP–FLL	Islip to Fort Lauderdale	45	53.3%	53.8 min	2.2%
ISP–RSW	Islip to Fort Myers	6	33.3%	46.7 min	0.0%

By scheduled departure hour

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

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

Delay causes

BTS cause category	Share of delay minutes	National, Dec 2025	Minutes
Air carrier	33.7%	33.3%	4,254
Late-arriving aircraft	43.8%	41.1%	5,537
National Aviation System	20.9%	19.1%	2,639
Extreme weather	1.7%	6.4%	211
Security	0.0%	0.2%	0

12,641 delay minutes on 158 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 December 2025?

62.2% of 458 scheduled domestic departures left less than 15 minutes late, and 62.9% reached their destination on time. The national figures that month were 72.0% and 71.9%.

How does that compare with a year earlier?

In December 2024, 68.1% of 432 departures left on time and 0.7% were cancelled, against 62.2% and 2.4% in December 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for December 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.