Air travel

How often are flights at Denver (DEN) late?

In the 12 months through August 2026, 24.1% of flights leaving Denver (DEN) left 15 or more minutes late, the 24th most of the 102 U.S. airports with at least 10,000 departures, against 22.9% of all U.S. flights. Airlines cancelled 0.8% of its scheduled departures (1.9% nationwide), the 9th fewest of the 102. Its worst month was August 2026, when 33.2% left late. Flights scheduled to leave in the 6 p.m. hour were late most often (44.7%), and those in the 6 a.m. hour least often (6.4%).

Left 15+ minutes late

24.1%

The 24th most of 102 airports

Cancelled

0.8%

The 9th fewest of 102 airports

Worst month

August 2026

33.2% left late

Flights leaving Denver (DEN) 15+ minutes late, each month

The interactive chart needs JavaScript. The numbers are in the tables below.

Flights leaving Denver (DEN) 15+ minutes late, by scheduled departure hour

The interactive chart needs JavaScript. The numbers are in the tables below.

Hours are local time at Denver. Delays build through the day as late planes make their next flights late too. Hours with fewer than about one flight a day are left out.

The numbers

Departures from Denver (DEN) each month and each scheduled departure hour.

Flights leaving Denver (DEN) by month
Month Scheduled Left late Cancelled
September 2025 26,548 19.6% 0.1%
October 2025 27,763 19.5% 0.1%
November 2025 25,280 16.9% 1.4%
December 2025 26,026 27.7% 0.6%
January 2026 24,484 18.8% 1.7%
February 2026 23,046 19.7% 0.9%
March 2026 27,089 25.4% 1.5%
April 2026 25,345 18.5% 0.3%
May 2026 27,406 23.9% 0.3%
June 2026 28,634 31.3% 0.4%
July 2026 29,503 31.1% 0.8%
August 2026 28,557 33.2% 1.3%
Flights leaving Denver (DEN) by departure hour
Departure hour Scheduled Left late Cancelled
Before 6 a.m. 4,492 6.8% 0.5%
6 a.m. 8,785 6.4% 0.9%
7 a.m. 17,126 9.5% 0.7%
8 a.m. 18,048 10.3% 0.6%
9 a.m. 24,168 13.6% 0.6%
10 a.m. 20,420 19.3% 0.5%
11 a.m. 31,656 17.6% 0.5%
Noon 12,856 24.7% 0.9%
1 p.m. 28,601 19.6% 0.7%
2 p.m. 12,093 30.5% 1.2%
3 p.m. 17,524 27.0% 0.9%
4 p.m. 15,220 31.3% 1.0%
5 p.m. 30,369 29.4% 0.9%
6 p.m. 12,193 44.7% 1.1%
7 p.m. 27,990 36.5% 0.7%
8 p.m. 20,304 37.2% 1.0%
9 p.m. 9,903 34.1% 0.8%
10 p.m. 3,410 39.6% 1.1%
11 p.m. 4,523 24.2% 1.6%

Source and notes

U.S. Bureau of Transportation Statistics, Airline On-Time Performance (Reporting Carrier On-Time Performance, 1987–present) (Public domain (U.S. government work)). Data from September 2025 through August 2026.

These are domestic flights of the large U.S. airlines that report to the Bureau of Transportation Statistics, including the regional airlines that fly for them. A flight is late when it leaves its gate 15 or more minutes after its scheduled time, out of the flights that left; cancellations are out of the flights scheduled. BTS posts each month about two months after it ends, and this page moves on a month when it does.