Best Time to Fly MIA to MDW: On-Time Stats by Hour & Airline
Miami International → Chicago Midway International
Data through July 2026 · Last updated October 18, 2026
503 flights were scheduled from Miami (MIA) to Chicago (MDW) in the last 12 months, and 68.4% of those that flew arrived on time, 9.3 points below the US average of 77.6%.
Frontier Airlines was the most punctual of the 2 airlines on the route at 77.8%, while Southwest Airlines trailed at 67.0%.
April has been the best month (79% on time) and Saturday the weakest day of the week (65%).
1.6% of flights were cancelled, versus 1.8% nationally.
MIA to MDW 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 |
|---|---|---|---|---|
| Frontier Airlines | 77.8% | 68 min | 1.6% | 64 |
| Southwest Airlines | 67.0% | 66 min | 1.6% | 439 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly MIA to MDW
On-time arrival % by scheduled departure hour (local time), 1,144 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 94.4% | 0.0% | 36 |
| 6am–7am | 87.3% | 3.6% | 196 |
| 7am–8am | 96.0% | 0.0% | 76 |
| 8am–9am | Limited data | 14 | |
| 9am–10am | Limited data | 7 | |
| 10am–11am | Limited data | 2 | |
| 11am–12pm | 75.3% | 0.0% | 73 |
| 12pm–1pm | 66.4% | 1.7% | 115 |
| 1pm–2pm | 59.1% | 0.0% | 44 |
| 2pm–3pm | 79.6% | 1.1% | 94 |
| 3pm–4pm | 68.6% | 0.0% | 86 |
| 4pm–5pm | 62.4% | 0.0% | 133 |
| 5pm–6pm | 56.2% | 0.9% | 107 |
| 6pm–7pm | 56.9% | 0.8% | 121 |
| 7pm–8pm | Limited data | 31 | |
| 8pm–9pm | Limited data | 4 | |
| 9pm–10pm | Limited data | 5 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on MIA to MDW
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) | Limited data | 25 | ||
| Christmas & New Year (Dec 20 - Jan 3) | 52.7% | -20.8 pts | 3.5% | 57 |
| Summer peak (Jun 15 - Aug 15) | 68.7% | -4.8 pts | 2.6% | 151 |
| All other days | 73.5% | — | 0.9% | 911 |
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).