Nantucket Memorial in September 2025

73.4%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 September 2025, reporting carriers scheduled 177 domestic departures from Nantucket Memorial (ACK). 73.4% left less than 15 minutes late and 68.4% reached their destination on time; 1.1% were cancelled.

Nationally that month, 83.1% of flights departed on time and 82.8% arrived on time, so ACK departures were 9.7 points below the national departure figure.

A year earlier, in September 2024, the airport had 175 departures with 88.6% leaving on time: a change of −15.2 points, with flights up 1%.

Flights arriving at ACK that month were on time 83.1% of the time (177 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, national aviation system 70%, late-arriving aircraft 22% and air carrier 8%.

On time 68.4%
Arrived 15+ minutes late 29.9%
Cancelled 1.1%
Diverted 0.6%

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

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

Measure	Sep 2025	Sep 2024	ACK, 12 months to Jul 2026	All reported flights, Sep 2025
Departed on time	73.4%	88.6%	73.0%	83.1%
Arrived on time	68.4%	86.3%	69.6%	82.8%
Cancelled	1.1%	0.6%	5.3%	0.5%
Average departure delay (late minutes only)	18.3 min	7.9 min	20.9 min	12.2 min
Scheduled departures a day	6	6	5	18,748
Scheduled departures	177	175	1,690	562,439

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
B6 JetBlue Airways	148	84%	70.9%	10.0 min	0.0%
YX Republic Airline	29	16%	55.2%	19.5 min	6.9%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ACK–JFK	Nantucket to New York	39	76.9%	9.0 min	0.0%
ACK–LGA	Nantucket to New York	38	73.7%	6.2 min	5.3%
ACK–DCA	Nantucket to Washington	34	64.7%	12.1 min	0.0%
ACK–BOS	Nantucket to Boston	32	37.5%	35.6 min	0.0%
ACK–HPN	Nantucket to White Plains	32	87.5%	-5.2 min	0.0%
ACK–PHL	Nantucket to Philadelphia	2	50.0%	19.0 min	0.0%

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), September 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Sep 2025	Minutes
Air carrier	8.2%	34.3%	278
Late-arriving aircraft	22.0%	37.4%	743
National Aviation System	69.7%	22.6%	2,351
Extreme weather	0.0%	5.6%	0
Security	0.0%	0.1%	0

3,372 delay minutes on 53 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 September 2025?

73.4% of 177 scheduled domestic departures left less than 15 minutes late, and 68.4% reached their destination on time. The national figures that month were 83.1% and 82.8%.

How does that compare with a year earlier?

In September 2024, 88.6% of 175 departures left on time and 0.6% were cancelled, against 73.4% and 1.1% in September 2025.

Provenance

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