Carrier route record
AADEN→MIA
American Airlines · Denver to Miami
- Flights
- 886
- Period
- July 2025 to June 2026
- Share of route
- 36%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with American Airlines.
American on DEN to MIA lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by close to two hours on average. That is a workable record, not a spotless one. That rests on 886 flights, with a median arrival 10 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate American on DEN to MIA from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.6%
Arrivals under 15 minutes late, of 876 completed flights
Avg delay
102 min
Across delayed arrivals only, not all flights
Cancelled
1.02%
National rate is 1.81%
Whole route
74.0%
Every carrier on DEN to MIA, 2,490 flights
These figures cover 886 flights between July 2025 and June 2026. Beyond the headline rate, 9.0% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
American against every carrier on DEN to MIA
American flew 886 of the 2,490 flights on DEN to MIA, about 36% of it. Its 76.6% on time is 3 points better than the route as a whole, which runs 74.0%. Ranked by on-time rate it is first of four carriers on the route, where the range runs from American at 76.6% to Southwest at 63.2%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlines (this page) | 886 | 76.6% | 102 min | 1.02% | B |
| United Airlines | 932 | 75.4% | 64 min | 0.11% | B+ |
| Frontier Airlinesthin sample | 349 | 73.6% | 59 min | 1.15% | C |
| Southwest Airlinesthin sample | 323 | 63.2% | 51 min | 0.62% | D+ |
Departure window
When American runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am113 flights84.7%
- 8am–11am46 flights76.1%
- 11am–2pm270 flights79.0%
- 2pm–5pm92 flights69.2%
- 5pm–8pm—
- 8pm–5am365 flights74.2%
Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 84.7% of the time, against 69.2% for the afternoon window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8pm–5am window is the busiest, with 365 flights scheduled in it.
Across the year
American on DEN to MIA through the year
August is the worst month at 54.8% on time, 38 points below February, the best at 92.9%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. January was the busiest month here, with 93 flights.
Across the week, Tuesday is the strongest day at 82.0% on time and Friday the weakest at 71.4%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why American runs late on this route
One category carries most of the weight here. Carrier accounts for 51% of the 21,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 51%Carrier
- 37%Late-arriving aircraft
- 10%National Airspace System
- 2%Extreme weather
- 0%Security
37% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 21,000 reported delay minutes here, that single category outweighs weather by 16 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 20,974 reported delay minutes.
The largest share of delay minutes, 51%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 11,000 of the 21,000 delay minutes reported here.
Cancellations sit at 1.02% against a national 1.81%, which is ordinary. Diversions add another 0.11%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.0% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 1,709 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg runs 75.7% on time across 885 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 886 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking American on DEN to MIA
Put together: treat all of this as provisional. 886 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 76.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 876 completed flights over 12 months sit behind that.
Related
Where to go next
- DEN to MIA, every carrier
- American on MIA to DEN, the return leg
- United Airlines on DEN to MIA75.4%
- Frontier Airlines on DEN to MIA73.6%
- Southwest Airlines on DEN to MIA63.2%
- American Airlines network-wide record
- Denver International (DEN) delay statistics
- Miami International (MIA) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.