ON TIMEBOARD

DEN → BHM on time

Denver (Denver, CO) to Birmingham-Shuttlesworth (Birmingham, AL). Every scheduled flight, September 2025 to August 2026.

On time
72%
arrived < 15 min late
Cancelled
0.3%
1,236 flights
Typical arrival
−1 min
median vs schedule
When late
+68 min
average delay
Flights / day
3
2 airlines

72% of flights from Denver to Birmingham arrived on time over the past 12 months. That is worse than the typical U.S. route. The 10 a.m. departures ran on time 79% of the time; the 5 p.m. ones 75%. Most reliable airline: United Airlines (79%). 9% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for DEN → BHM: when a flight was late, it was under 45 minutes late 53% of the time. About 1 in 11 flights landed an hour or more late, and 1 in 69 three hours or more; 0.3% were cancelled outright.

Share of all 1,236 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
United Airlines72779%0.3%−9 min5.9%+74 minSkyWest 83%, United Airlines 17%
Southwest Airlines50963%0.4%+6 min13.4%+63 minSouthwest Airlines

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at DEN). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%10 a.m. departures: 79% on time (453 flights)7910a11 a.m. departures: too few flights (54 flights)11anoon departures: too few flights12p1 p.m. departures: too few flights (17 flights)1p2 p.m. departures: too few flights (8 flights)2p3 p.m. departures: too few flights (2 flights)3p4 p.m. departures: too few flights (60 flights)4p5 p.m. departures: 75% on time (405 flights)755p6 p.m. departures: too few flights (46 flights)6p7 p.m. departures: too few flights (93 flights)7p8 p.m. departures: too few flights (57 flights)8p9 p.m. departures: too few flights (22 flights)9p
DEN → BHM, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

By airline and hour

DepartsUnited AirlinesSouthwest Airlines
10 a.m.81%75%
5 p.m.76%—

Last flight of the day

On DEN → BHM, each airline's last flight of the day was cancelled 0.4% of the time, against 0.4% for its earlier flights, about the same. It arrived 3+ hours late 2.4% of the time (earlier flights: 0.6%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
United Airlines5:50 p.m.0.3%2.2%0.3%first flight 10:15 a.m.
Southwest Airlines7:25 p.m.0.7%2.8%0.7%first flight 10:55 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

By month

Each calendar month pooled over 2023–2026. Best: October (78%). Worst: June (56%).

40%70%100%Jan: 73% on time (279 flights)73JanFeb: 77% on time (252 flights)77FebMar: 76% on time (297 flights)76MarApr: 71% on time (292 flights)71AprMay: 65% on time (301 flights)65MayJun: 56% on time (296 flights)56JunJul: 66% on time (305 flights)66JulAug: 61% on time (297 flights)61AugSep: 72% on time (268 flights)72SepOct: 78% on time (279 flights)78OctNov: 75% on time (265 flights)75NovDec: 77% on time (277 flights)77Dec

By day of week

DayFlightsOn timeCancelled
Monday18171%1.1%
Tuesday18180%0.0%
Wednesday18173%0.0%
Thursday17669%0.0%
Friday17767%0.6%
Saturday15972%0.6%
Sunday18173%0.0%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Late inbound plane 45%Airline (crew, maintenance, ops) 30%Air traffic & airport (NAS) 21%Severe weather 4%

Cancellations: weather 3 · air traffic/airport 1

Month by month

40%70%100%Sep 2023Jan 2024Jan 2025Jan 2026Mar 2026: 74% on time, 2.6% cancelledApr 2026: 77% on time, 0.0% cancelledMay 2026: 68% on time, 0.0% cancelledJun 2026: 58% on time, 0.0% cancelledJul 2026: 66% on time, 0.8% cancelledAug 2026: 55% on time, 0.0% cancelled
Share of flights on time, by month (hover a point for cancellations)
DEN → BHM, monthly on-time and cancellation rate.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
UA 58155:30 p.m.30779%0.3%−11 minSkyWest

Worst days in the past year

DateFlightsOn timeCancelled
Jun 22, 202640%0
Mar 6, 202640%1
Jun 28, 202640%0
May 19, 202640%0
Dec 11, 202530%0

Questions

How often are flights from DEN to BHM on time?

72% of 1,236 scheduled flights from Denver, CO to Birmingham, AL arrived within 15 minutes of schedule between September 2025 and August 2026. 0.3% were cancelled.

What is the best time of day to fly DEN to BHM?

Flights scheduled to leave at 10 a.m. were the most reliable (79% on time). The 5 p.m. departures were the least (75%).

Which airline is most on time from DEN to BHM?

United Airlines: 79% of its 727 flights on the route arrived on time. Southwest Airlines: 63%.

What month has the most delays from DEN to BHM?

June (56% on time). The best month is October (78%), over 2023–2026.

Is the last flight of the day from DEN to BHM more likely to be cancelled?

Not much. Each airline's last DEN–BHM flight of the day was cancelled 0.4% of the time over the past year, against 0.4% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.