Denver International in December 2025

71.9%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 December 2025, reporting carriers scheduled 26,026 domestic departures from Denver International (DEN). 71.9% left less than 15 minutes late and 73.5% reached their destination on time; 0.6% were cancelled.

Nationally that month, 72.0% of flights departed on time and 71.9% arrived on time, so DEN departures were level with the national departure figure.

A year earlier, in December 2024, the airport had 25,905 departures with 81.5% leaving on time: a change of −9.6 points, with flights up 0%.

Flights arriving at DEN that month were on time 74.5% of the time (26,007 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 44%, air carrier 34% and national aviation system 17%.

On time 73.5%
Arrived 15+ minutes late 25.5%
Cancelled 0.6%
Diverted 0.3%

Every scheduled departure from DEN in December 2025, judged by arrival at the destination.

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

Measure	Dec 2025	Dec 2024	DEN, 12 months to Jul 2026	All reported flights, Dec 2025
Departed on time	71.9%	81.5%	75.7%	72.0%
Arrived on time	73.5%	84.1%	76.1%	71.9%
Cancelled	0.6%	0.3%	0.7%	1.5%
Average departure delay (late minutes only)	20.0 min	12.0 min	16.5 min	21.2 min
Scheduled departures a day	868	864	875	19,410
Scheduled departures	26,026	25,905	319,208	582,304

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
UA United Airlines	8,548	33%	77.4%	7.1 min	0.2%
WN Southwest Airlines	7,415	28%	67.9%	13.7 min	0.6%
OO SkyWest Airlines	6,240	24%	75.5%	12.4 min	0.9%
F9 Frontier Airlines	1,733	7%	75.0%	6.0 min	0.8%
DL Delta Air Lines	996	4%	71.5%	12.2 min	2.4%
AA American Airlines	723	3%	73.4%	13.6 min	0.8%
AS Alaska Airlines	204	1%	63.7%	14.7 min	0.0%
B6 JetBlue Airways	110	0%	70.0%	35.0 min	3.6%
MQ Envoy Air	39	0%	64.1%	15.7 min	0.0%
G4 Allegiant Air	18	0%	61.1%	19.8 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
DEN–PHX	Denver to Phoenix	775	75.7%	7.9 min	0.5%
DEN–LAX	Denver to Los Angeles	651	74.5%	9.3 min	0.6%
DEN–SLC	Denver to Salt Lake City	628	71.8%	12.2 min	0.3%
DEN–LAS	Denver to Las Vegas	560	74.3%	7.4 min	0.4%
DEN–SAN	Denver to San Diego	538	69.9%	10.4 min	0.6%
DEN–DFW	Denver to Dallas/Fort Worth	481	75.1%	7.4 min	0.0%
DEN–SEA	Denver to Seattle	468	58.8%	22.7 min	0.9%
DEN–ATL	Denver to Atlanta	459	73.2%	6.7 min	1.1%
DEN–SFO	Denver to San Francisco	457	63.9%	18.1 min	0.2%
DEN–AUS	Denver to Austin	450	78.0%	10.3 min	0.0%
DEN–COS	Denver to Colorado Springs	441	75.1%	12.9 min	1.1%
DEN–MSP	Denver to Minneapolis	438	68.0%	14.9 min	0.5%

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), December 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Dec 2025	Minutes
Air carrier	34.4%	33.3%	155,652
Late-arriving aircraft	43.6%	41.1%	197,474
National Aviation System	16.9%	19.1%	76,628
Extreme weather	4.8%	6.4%	21,759
Security	0.3%	0.2%	1,529

453,042 delay minutes on 6,635 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 DEN on time in December 2025?

71.9% of 26,026 scheduled domestic departures left less than 15 minutes late, and 73.5% reached their destination on time. The national figures that month were 72.0% and 71.9%.

How does that compare with a year earlier?

In December 2024, 81.5% of 25,905 departures left on time and 0.3% were cancelled, against 71.9% and 0.6% in December 2025.

Provenance

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