FlightRecord

Chicago (MDW) to Boston (BOS): On-Time Performance

Data through May 2026

Chicago (MDW) to Boston (BOS) effectively runs on two schedules. In January 2025, 90% of arrivals were on time; in March 2026 that fell to 55% — a 36-point seasonal swing. Across the full period the route averages 71% on-time against a national 78%. Morning departures also hold up better than evening ones (88% vs 62%), which matters most in the rough months.

On-time
71%
arrived <15 min late
Avg delay
19 min
completed flights
Cancelled
0.7%
Flights/day
3.8
last 12 months
Duration
2h 16m
scheduled
Distance
861 mi

Monthly on-time trend

Monthly on-time percentage for MDW to BOS flights50%75%100%June 2024: 61% on-time (160 flights)61Jun 2024July 2024: 69% on-time (170 flights)69August 2024: 66% on-time (144 flights)66September 2024: 81% on-time (136 flights)81Sep 2024October 2024: 89% on-time (139 flights)89November 2024: 83% on-time (89 flights)83December 2024: 70% on-time (91 flights)70Dec 2024January 2025: 90% on-time (71 flights)90February 2025: 82% on-time (66 flights)82March 2025: 79% on-time (83 flights)79Mar 2025April 2025: 87% on-time (94 flights)87May 2025: 61% on-time (101 flights)61June 2025: 64% on-time (157 flights)64Jun 2025July 2025: 68% on-time (172 flights)68August 2025: 74% on-time (134 flights)74September 2025: 56% on-time (128 flights)56Sep 2025October 2025: 62% on-time (139 flights)62November 2025: 74% on-time (88 flights)74December 2025: 73% on-time (90 flights)73Dec 2025January 2026: 79% on-time (69 flights)79February 2026: 80% on-time (63 flights)80March 2026: 55% on-time (113 flights)55Mar 2026April 2026: 72% on-time (119 flights)72May 2026: 72% on-time (123 flights)72

Best time to fly from MDW to BOS

Aim for departures around 6 a.m. (95% on-time); avoid 9 p.m. departures (46%).

On-time percentage by scheduled departure hour, MDW to BOS5 a.m.: 95% on-time (100 flights)56 a.m.: 95% on-time (207 flights)67 a.m.: 90% on-time (166 flights)78 a.m.: 86% on-time (209 flights)89 a.m.: 86% on-time (240 flights)910 a.m.: 87% on-time (141 flights)1011 a.m.: 54% on-time (27 flights)1112 p.m.: 68% on-time (152 flights)121 p.m.: 58% on-time (239 flights)132 p.m.: 59% on-time (185 flights)143 p.m.: 51% on-time (135 flights)154 p.m.: 48% on-time (85 flights)165 p.m.: 70% on-time (127 flights)176 p.m.: 64% on-time (311 flights)187 p.m.: 57% on-time (192 flights)198 p.m.: 63% on-time (163 flights)209 p.m.: 46% on-time (51 flights)21scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday68%21 min
Tuesday76%17 min
Wednesday72%15 min
Thursday68%23 min
Friday70%21 min
Saturdaybest81%10 min
Sunday66%22 min

What causes delays on this route

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

  • Late-arriving aircraft31%
  • Airline operations32%
  • National airspace system35%
  • Weather2%
  • Security1%

Frequently asked questions

How often are flights from MDW to BOS delayed?
29% of MDW–BOS 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 19 minutes.
What is the best time of day to fly from MDW to BOS?
Departures around 6 a.m. have the best record (95% on-time), while departures around 9 p.m. have the worst (46%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from MDW to BOS?
The scheduled MDW–BOS flight time averages 2h 16m over 861 miles. Actual arrival times vary — flights on this route land 15+ minutes late 29% of the time.
How often are MDW to BOS flights cancelled?
0.7% 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 BOS?
March 2026 was the roughest month in this dataset, with only 55% of arrivals on time. The best was January 2025 at 90%. If your dates are flexible, that 36-point gap is worth planning around.

Based on 2,739 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.