FlightRecord

Chicago (MDW) to San Francisco (SFO): On-Time Performance

Data through May 2026

Chicago (MDW) to San Francisco (SFO) effectively runs on two schedules. In October 2024, 81% of arrivals were on time; in May 2026 that fell to 19% — a 62-point seasonal swing. Across the full period the route averages 59% on-time against a national 78%. Morning departures also hold up better than evening ones (66% vs 46%), which matters most in the rough months.

On-time
59%
arrived <15 min late
Avg delay
26 min
completed flights
Cancelled
0.9%
Flights/day
1.2
last 12 months
Duration
4h 36m
scheduled
Distance
1,855 mi

Monthly on-time trend

Monthly on-time percentage for MDW to SFO flights50%75%100%June 2024: 42% on-time (63 flights)42Jun 2024July 2024: 64% on-time (71 flights)64August 2024: 50% on-time (52 flights)50September 2024: 72% on-time (43 flights)72Sep 2024October 2024: 81% on-time (43 flights)81November 2024: 60% on-time (30 flights)60December 2024: 77% on-time (31 flights)77Dec 2024January 2025: 71% on-time (14 flights)71February 2025: 68% on-time (19 flights)68March 2025: 62% on-time (29 flights)62Mar 2025April 2025: 70% on-time (30 flights)70May 2025: 81% on-time (31 flights)81June 2025: 60% on-time (30 flights)60Jun 2025July 2025: 60% on-time (31 flights)60August 2025: 81% on-time (31 flights)81September 2025: 80% on-time (30 flights)80Sep 2025October 2025: 55% on-time (31 flights)55November 2025: 72% on-time (30 flights)72December 2025: 55% on-time (31 flights)55Dec 2025January 2026: 71% on-time (14 flights)71February 2026: 84% on-time (19 flights)84March 2026: 57% on-time (56 flights)57Mar 2026April 2026: 24% on-time (60 flights)24May 2026: 19% on-time (62 flights)19

Best time to fly from MDW to SFO

Aim for departures around 8 a.m. (78% on-time); avoid 10 a.m. departures (35%).

On-time percentage by scheduled departure hour, MDW to SFO8 a.m.: 78% on-time (105 flights)89 a.m.: 71% on-time (98 flights)910 a.m.: 35% on-time (82 flights)1011 a.m.: 75% on-time (98 flights)1112 p.m.: 67% on-time (50 flights)121 p.m.: 44% on-time (45 flights)132 p.m.: 63% on-time (24 flights)143 p.m.: 66% on-time (39 flights)154 p.m.: 60% on-time (80 flights)166 p.m.: 61% on-time (51 flights)187 p.m.: 46% on-time (22 flights)198 p.m.: 50% on-time (34 flights)209 p.m.: 37% on-time (105 flights)2110 p.m.: 42% on-time (31 flights)22scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday59%23 min
Tuesday62%24 min
Wednesday53%26 min
Thursday60%29 min
Friday54%29 min
Saturdaybest65%22 min
Sunday59%25 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft34%
  • Airline operations30%
  • National airspace system32%
  • Weather4%

Frequently asked questions

How often are flights from MDW to SFO delayed?
41% of MDW–SFO flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 26 minutes.
What is the best time of day to fly from MDW to SFO?
Departures around 8 a.m. have the best record (78% on-time), while departures around 10 a.m. have the worst (35%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from MDW to SFO?
The scheduled MDW–SFO flight time averages 4h 36m over 1,855 miles. Actual arrival times vary — flights on this route land 15+ minutes late 41% of the time.
How often are MDW to SFO flights cancelled?
0.9% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
What is the worst month to fly from MDW to SFO?
May 2026 was the roughest month in this dataset, with only 19% of arrivals on time. The best was October 2024 at 81%. If your dates are flexible, that 62-point gap is worth planning around.

Based on 881 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.