James M Cox/Dayton International in May 2025

77.5%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 737 domestic departures from James M Cox/Dayton International (DAY). 77.5% left less than 15 minutes late and 73.5% reached their destination on time; 1.8% were cancelled.

Nationally that month, 76.7% of flights departed on time and 75.4% arrived on time, so DAY departures were 0.8 points above the national departure figure.

A year earlier, in May 2024, the airport had 712 departures with 80.1% leaving on time: a change of −2.6 points, with flights up 4%.

Flights arriving at DAY that month were on time 69.7% of the time (739 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 41%, air carrier 31% and national aviation system 18%.

On time 73.5%
Arrived 15+ minutes late 24.3%
Cancelled 1.8%
Diverted 0.4%

Every scheduled departure from DAY 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	DAY, 12 months to Jul 2026	All reported flights, May 2025
Departed on time	77.5%	80.1%	78.8%	76.7%
Arrived on time	73.5%	77.4%	77.4%	75.4%
Cancelled	1.8%	1.8%	2.7%	1.0%
Average departure delay (late minutes only)	25.2 min	20.2 min	20.9 min	17.5 min
Scheduled departures a day	25	24	22	20,188
Scheduled departures	737	712	7,918	605,648

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
OH PSA Airlines	391	53%	68.3%	27.7 min	2.3%
OO SkyWest Airlines	168	23%	82.7%	0.1 min	1.2%
DL Delta Air Lines	118	16%	83.1%	-1.1 min	0.0%
G4 Allegiant Air	28	4%	39.3%	131.1 min	0.0%
YX Republic Airline	27	4%	85.2%	1.0 min	3.7%
MQ Envoy Air	5	1%	80.0%	-16.0 min	20.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
DAY–ORD	Dayton to Chicago	138	83.3%	1.3 min	1.4%
DAY–DFW	Dayton to Dallas/Fort Worth	124	70.2%	26.3 min	3.2%
DAY–CLT	Dayton to Charlotte	120	73.3%	38.7 min	0.8%
DAY–ATL	Dayton to Atlanta	118	83.1%	-1.1 min	0.0%
DAY–DCA	Dayton to Washington	118	59.3%	22.5 min	3.4%
DAY–PHL	Dayton to Philadelphia	34	73.5%	7.5 min	2.9%
DAY–DEN	Dayton to Denver	31	80.6%	-5.3 min	0.0%
DAY–LGA	Dayton to New York	26	88.5%	-1.0 min	3.8%
DAY–PGD	Dayton to Punta Gorda	10	60.0%	5.7 min	0.0%
DAY–PIE	Dayton to St. Petersburg	9	55.6%	236.8 min	0.0%
DAY–SFB	Dayton to Sanford	9	0.0%	164.7 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), May 2025.

Delay causes

BTS cause category	Share of delay minutes	National, May 2025	Minutes
Air carrier	31.4%	29.3%	6,131
Late-arriving aircraft	40.6%	37.8%	7,920
National Aviation System	17.8%	25.9%	3,470
Extreme weather	10.3%	6.9%	2,007
Security	0.0%	0.1%	0

19,528 delay minutes on 179 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 May 2025?

77.5% of 737 scheduled domestic departures left less than 15 minutes late, and 73.5% 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, 80.1% of 712 departures left on time and 1.8% were cancelled, against 77.5% and 1.8% 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 DAY · methodology · corrections.