Best Time to Fly MDW to SAN: On-Time Stats by Hour & Airline
Chicago Midway International → San Diego International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 72.2% of Chicago (MDW) to San Diego (SAN) flights arrived on time (1,092 scheduled flights). That is 5.4 points below the national average of 77.6%.
Southwest Airlines was the only reporting airline with regular flights on this route.
Over 24 months, Wednesday was the most reliable day (82% on time) and June the worst month (59%).
The cancellation rate was 1.4% (US average 1.8%).
MDW to SAN 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 |
|---|---|---|---|---|
| Southwest Airlines | 72.2% | 46 min | 1.4% | 1,092 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly MDW to SAN
On-time arrival % by scheduled departure hour (local time), 2,099 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 90.7% | 0.0% | 55 |
| 6am–7am | 89.9% | 0.0% | 172 |
| 7am–8am | 93.8% | 0.9% | 114 |
| 8am–9am | 84.2% | 0.0% | 341 |
| 9am–10am | 70.0% | 0.0% | 40 |
| 10am–11am | 67.0% | 1.1% | 184 |
| 11am–12pm | 70.3% | 0.0% | 92 |
| 12pm–1pm | 82.0% | 1.0% | 101 |
| 1pm–2pm | 83.2% | 0.0% | 113 |
| 2pm–3pm | 57.3% | 1.1% | 91 |
| 3pm–4pm | 75.7% | 1.4% | 71 |
| 4pm–5pm | 70.0% | 0.0% | 90 |
| 5pm–6pm | 63.3% | 1.6% | 61 |
| 6pm–7pm | 73.8% | 0.0% | 65 |
| 7pm–8pm | 80.2% | 0.0% | 124 |
| 8pm–9pm | 65.3% | 2.5% | 318 |
| 9pm–10pm | 50.0% | 7.5% | 67 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on MDW to SAN
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) | 73.5% | -4.5 pts | 5.6% | 36 |
| Christmas & New Year (Dec 20 - Jan 3) | 56.8% | -21.3 pts | 1.3% | 78 |
| Summer peak (Jun 15 - Aug 15) | 70.4% | -7.6 pts | 1.2% | 401 |
| All other days | 78.0% | — | 0.8% | 1,584 |
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).