Best Time to Fly ATL to MIA: On-Time Stats by Hour & Airline
Hartsfield-Jackson Atlanta International → Miami International
Data through July 2026 · Last updated October 18, 2026
6,268 flights were scheduled from Atlanta (ATL) to Miami (MIA) in the last 12 months, and 71.4% of those that flew arrived on time, 6.2 points below the US average of 77.6%.
Among 6 airlines, American Airlines led with 75.5% on time and Republic Airways was last with 63.6%.
Over 24 months, Wednesday was the most reliable day (81% on time) and July the worst month (61%).
The cancellation rate was 1.6% (US average 1.8%).
ATL to MIA on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| American Airlines | 75.5% | 91 min | 0.8% | 1,535 |
| Envoy Air | 74.6% | 75 min | 1.3% | 231 |
| Spirit Airlines | 73.9% | 97 min | 4.4% | 252 |
| Delta Air Lines | 71.1% | 55 min | 1.8% | 3,306 |
| Frontier Airlines | 64.3% | 96 min | 1.6% | 900 |
| Republic Airways | 63.6% | 68 min | 0.0% | 44 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly ATL to MIA
On-time arrival % by scheduled departure hour (local time), 12,678 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 92.3% | 1.2% | 505 |
| 6am–7am | 85.3% | 0.6% | 336 |
| 7am–8am | 86.3% | 1.2% | 1,196 |
| 8am–9am | 79.1% | 1.4% | 995 |
| 9am–10am | 77.2% | 1.2% | 932 |
| 10am–11am | 75.4% | 1.6% | 679 |
| 11am–12pm | 81.4% | 1.6% | 1,351 |
| 12pm–1pm | 75.7% | 1.0% | 503 |
| 1pm–2pm | 73.5% | 1.3% | 670 |
| 2pm–3pm | 63.2% | 1.4% | 484 |
| 3pm–4pm | 62.0% | 1.0% | 582 |
| 4pm–5pm | 59.4% | 1.2% | 853 |
| 5pm–6pm | 59.4% | 1.5% | 326 |
| 6pm–7pm | 65.4% | 2.3% | 751 |
| 7pm–8pm | 59.3% | 1.8% | 801 |
| 8pm–9pm | 57.2% | 1.1% | 642 |
| 9pm–10pm | 46.9% | 3.9% | 102 |
| 10pm–11pm | 67.2% | 2.2% | 875 |
| 11pm–12am | 58.7% | 3.2% | 95 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on ATL to MIA
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 69.7% | -5.4 pts | 0.4% | 236 |
| Christmas & New Year (Dec 20 - Jan 3) | 61.4% | -13.6 pts | 2.2% | 601 |
| Summer peak (Jun 15 - Aug 15) | 63.0% | -12.0 pts | 3.0% | 2,114 |
| All other days | 75.0% | — | 1.1% | 9,727 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).