Nantucket Memorial in July 2025

66.9%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 July 2025, reporting carriers scheduled 496 domestic departures from Nantucket Memorial (ACK). 66.9% left less than 15 minutes late and 59.7% reached their destination on time; 8.1% were cancelled.

Nationally that month, 69.7% of flights departed on time and 69.0% arrived on time, so ACK departures were 2.8 points below the national departure figure.

A year earlier, in July 2024, the airport had 479 departures with 70.6% leaving on time: a change of −3.7 points, with flights up 4%.

Flights arriving at ACK that month were on time 75.8% of the time (496 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, national aviation system 39%, air carrier 33% and late-arriving aircraft 27%.

On time 59.7%
Arrived 15+ minutes late 31.9%
Cancelled 8.1%
Diverted 0.4%

Every scheduled departure from ACK in July 2025, judged by arrival at the destination.

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

Measure	Jul 2025	Jul 2024	ACK, 12 months to Jul 2026	All reported flights, Jul 2025
Departed on time	66.9%	70.6%	73.0%	69.7%
Arrived on time	59.7%	69.3%	69.6%	69.0%
Cancelled	8.1%	5.4%	5.3%	2.5%
Average departure delay (late minutes only)	31.5 min	20.7 min	20.9 min	24.3 min
Scheduled departures a day	17	16	5	21,048
Scheduled departures	496	479	1,690	631,428

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
B6 JetBlue Airways	248	50%	63.7%	30.4 min	4.8%
YX Republic Airline	236	48%	55.9%	22.6 min	11.4%
OO SkyWest Airlines	8	2%	37.5%	141.3 min	12.5%
MQ Envoy Air	4	1%	75.0%	1.5 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ACK–LGA	Nantucket to New York	132	68.2%	25.1 min	6.1%
ACK–DCA	Nantucket to Washington	96	62.5%	5.1 min	11.5%
ACK–JFK	Nantucket to New York	93	51.6%	55.0 min	9.7%
ACK–BOS	Nantucket to Boston	62	62.9%	25.4 min	1.6%
ACK–HPN	Nantucket to White Plains	62	64.5%	21.2 min	4.8%
ACK–PHL	Nantucket to Philadelphia	35	34.3%	30.1 min	17.1%
ACK–ORD	Nantucket to Chicago	12	33.3%	101.9 min	16.7%
ACK–CLT	Nantucket to Charlotte	4	75.0%	1.5 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), July 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Jul 2025	Minutes
Air carrier	33.2%	31.1%	5,210
Late-arriving aircraft	26.5%	40.8%	4,159
National Aviation System	38.7%	20.7%	6,070
Extreme weather	1.5%	7.3%	242
Security	0.0%	0.1%	0

15,681 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 ACK on time in July 2025?

66.9% of 496 scheduled domestic departures left less than 15 minutes late, and 59.7% reached their destination on time. The national figures that month were 69.7% and 69.0%.

How does that compare with a year earlier?

In July 2024, 70.6% of 479 departures left on time and 5.4% were cancelled, against 66.9% and 8.1% in July 2025.

Provenance

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