James M Cox/Dayton International in September 2025

87.6%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 639 domestic departures from James M Cox/Dayton International (DAY). 87.6% left less than 15 minutes late and 85.8% reached their destination on time; 0.3% were cancelled.

Nationally that month, 83.1% of flights departed on time and 82.8% arrived on time, so DAY departures were 4.5 points above the national departure figure.

A year earlier, in September 2024, the airport had 666 departures with 87.7% leaving on time: a change of −0.1 points, with flights down 4%.

Flights arriving at DAY that month were on time 81.1% of the time (641 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 45%, air carrier 35% and national aviation system 19%.

On time 85.8%
Arrived 15+ minutes late 13.3%
Cancelled 0.3%
Diverted 0.6%

Every scheduled departure from DAY 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	DAY, 12 months to Jul 2026	All reported flights, Sep 2025
Departed on time	87.6%	87.7%	78.8%	83.1%
Arrived on time	85.8%	86.6%	77.4%	82.8%
Cancelled	0.3%	0.3%	2.7%	0.5%
Average departure delay (late minutes only)	12.2 min	10.5 min	20.9 min	12.2 min
Scheduled departures a day	21	22	22	18,748
Scheduled departures	639	666	7,918	562,439

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
OH PSA Airlines	434	68%	83.6%	0.5 min	0.5%
DL Delta Air Lines	127	20%	92.1%	-11.5 min	0.0%
UA United Airlines	36	6%	94.4%	-10.6 min	0.0%
MQ Envoy Air	27	4%	85.2%	-1.8 min	0.0%
G4 Allegiant Air	9	1%	66.7%	9.2 min	0.0%
YX Republic Airline	6	1%	83.3%	-10.0 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
DAY–ATL	Dayton to Atlanta	127	92.1%	-11.5 min	0.0%
DAY–CLT	Dayton to Charlotte	120	88.3%	-2.8 min	0.0%
DAY–DFW	Dayton to Dallas/Fort Worth	119	78.2%	9.9 min	0.0%
DAY–ORD	Dayton to Chicago	116	86.2%	-5.4 min	1.7%
DAY–DCA	Dayton to Washington	86	79.1%	3.1 min	0.0%
DAY–DEN	Dayton to Denver	30	96.7%	-12.7 min	0.0%
DAY–PHL	Dayton to Philadelphia	30	90.0%	-12.3 min	0.0%
DAY–PIE	Dayton to St. Petersburg	9	66.7%	9.2 min	0.0%
DAY–LGA	Dayton to New York	2	100.0%	-13.5 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	34.5%	34.3%	2,600
Late-arriving aircraft	45.4%	37.4%	3,421
National Aviation System	19.1%	22.6%	1,436
Extreme weather	1.0%	5.6%	74
Security	0.0%	0.1%	0

7,531 delay minutes on 85 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 DAY on time in September 2025?

87.6% of 639 scheduled domestic departures left less than 15 minutes late, and 85.8% 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, 87.7% of 666 departures left on time and 0.3% were cancelled, against 87.6% and 0.3% 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 DAY · methodology · corrections.