Delta Air Lines in September 2025

87.4%arrived 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, Delta Air Lines (DL) reported 84,875 scheduled domestic flights. 87.4% arrived on time, 0.1% were cancelled and 0.2% diverted.

All reporting carriers together recorded 82.8% on time and 0.5% cancelled that month, so the carrier was 4.6 points above the combined figure.

A year earlier, in September 2024, it reported 84,545 flights with 86.6% on time: a change of +0.8 points.

Of the delay minutes that carriers assigned to a BTS cause category that month, air carrier 48%, late-arriving aircraft 28% and national aviation system 22%.

On time 87.4%
Arrived 15+ minutes late 12.3%
Cancelled 0.1%
Diverted 0.2%

Every scheduled domestic flight reported by Delta Air Lines in September 2025.

September 2025 against a year earlier, the carrier's year and all carriers

Measure	Sep 2025	Sep 2024	DL, 12 months to Jul 2026	All carriers, Sep 2025
Arrived on time	87.4%	86.6%	79.9%	82.8%
Departed on time	87.7%	86.8%	80.6%	83.1%
Cancelled	0.1%	0.4%	1.7%	0.5%
Average arrival delay	-1.9 min	-1.5 min	3.9 min	2.3 min
Scheduled flights a day	2,829	2,818	2,846	18,748
Scheduled flights	84,875	84,545	1,038,644	562,439

143 airports and 946 routes had DL flights that month.

Busiest airports that month

Airport	Departures	On time	Avg arrival delay	Cancelled
ATL Atlanta	19,675	87.0%	-0.9 min	0.0%
MSP Minneapolis	5,494	86.8%	-2.4 min	0.0%
DTW Detroit	4,813	86.9%	-0.6 min	0.0%
SLC Salt Lake City	4,393	86.9%	-0.1 min	0.1%
LAX Los Angeles	3,028	87.4%	-2.5 min	0.1%
SEA Seattle	2,718	85.4%	1.1 min	0.1%
JFK New York	2,560	83.9%	-3.3 min	0.3%
LGA New York	2,524	83.8%	2.2 min	0.2%
BOS Boston	2,199	74.8%	11.6 min	0.6%
MCO Orlando	1,525	87.5%	-3.4 min	0.0%
LAS Las Vegas	1,250	84.2%	1.1 min	0.0%
SFO San Francisco	1,141	82.4%	2.5 min	0.0%
AUS Austin	1,069	88.8%	-2.8 min	0.3%
DFW Dallas/Fort Worth	1,024	83.5%	0.9 min	0.6%
ORD Chicago	1,012	81.1%	3.9 min	0.2%

By scheduled departure hour

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

Share of DL flights that arrived on time, by scheduled departure hour (local time at each origin), September 2025.

Delay causes

BTS cause category	Share of delay minutes	All carriers, Sep 2025	Minutes
Air carrier	47.5%	34.3%	335,946
Late-arriving aircraft	28.2%	37.4%	199,290
National Aviation System	21.6%	22.6%	152,467
Extreme weather	2.7%	5.6%	18,945
Security	0.1%	0.1%	665

707,313 delay minutes on 10,481 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

What share of Delta Air Lines flights were on time in September 2025?

87.4% of 84,875 scheduled domestic flights arrived less than 15 minutes late; all reporting carriers together recorded 82.8% that month.

How does that compare with a year earlier?

In September 2024 the carrier reported 84,545 flights with 86.6% on time and 0.4% cancelled, against 87.4% and 0.1% in September 2025.

Provenance

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