Best Time to Fly MDW to SFO: On-Time Stats by Hour & Airline
Chicago Midway International → San Francisco International
Data through July 2026 · Last updated October 18, 2026
485 flights were scheduled from Chicago (MDW) to San Francisco (SFO) in the last 12 months, and 48.1% of those that flew arrived on time, 29.5 points below the US average of 77.6%.
Southwest Airlines was the only reporting airline with regular flights on this route.
Over 24 months, Saturday was the most reliable day (67% on time) and June the worst month (39%).
The cancellation rate was 1.2% (US average 1.8%).
MDW to SFO 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 | 48.1% | 56 min | 1.2% | 485 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly MDW to SFO
On-time arrival % by scheduled departure hour (local time), 868 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | Limited data | 9 | |
| 8am–9am | 78.1% | 0.0% | 105 |
| 9am–10am | 63.6% | 0.0% | 66 |
| 10am–11am | 27.8% | 0.8% | 134 |
| 11am–12pm | 74.5% | 0.0% | 98 |
| 12pm–1pm | 68.8% | 2.0% | 50 |
| 1pm–2pm | 44.4% | 0.0% | 45 |
| 2pm–3pm | Limited data | 24 | |
| 3pm–4pm | 67.6% | 2.6% | 39 |
| 4pm–5pm | 71.1% | 0.0% | 45 |
| 5pm–6pm | Limited data | 8 | |
| 6pm–7pm | 59.5% | 0.0% | 42 |
| 7pm–8pm | Limited data | 22 | |
| 8pm–9pm | 51.5% | 0.0% | 33 |
| 9pm–10pm | 41.2% | 3.0% | 135 |
| 10pm–11pm | Limited data | 13 | |
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 SFO
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 | 13 | ||
| Christmas & New Year (Dec 20 - Jan 3) | 50.0% | -10.2 pts | 0.0% | 30 |
| Summer peak (Jun 15 - Aug 15) | 44.5% | -15.6 pts | 1.1% | 184 |
| All other days | 60.2% | — | 0.6% | 641 |
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).