FlightRecord

Atlanta (ATL) to Chicago (MDW): On-Time Performance

Data through May 2026

When you fly ATL to MDW matters as much as anything else about the booking: the route swung from 90% on-time in September 2025 to just 64% in May 2026. Across the full period the route averages 78% on-time against a national 78%. Morning departures also hold up better than evening ones (87% vs 69%), which matters most in the rough months.

On-time
78%
arrived <15 min late
Avg delay
15 min
completed flights
Cancelled
1.3%
Flights/day
9.7
last 12 months
Duration
1h 56m
scheduled
Distance
591 mi

Best airline from ATL to MDW

3 airlines flew this route regularly between 2024-06 and 2026-05.

AirlineOn-timeAvg delayCancelledFlights
Delta Air Linesmost reliable82%11 min1.7%2,983
Southwest Airlines79%13 min1.0%3,219
Frontier Airlines65%33 min1.2%1,107

Monthly on-time trend

Monthly on-time percentage for ATL to MDW flights50%75%100%June 2024: 79% on-time (331 flights)79Jun 2024July 2024: 70% on-time (339 flights)70August 2024: 85% on-time (348 flights)85September 2024: 86% on-time (330 flights)86Sep 2024October 2024: 87% on-time (342 flights)87November 2024: 82% on-time (330 flights)82December 2024: 80% on-time (304 flights)80Dec 2024January 2025: 79% on-time (279 flights)79February 2025: 82% on-time (246 flights)82March 2025: 83% on-time (303 flights)83Mar 2025April 2025: 79% on-time (301 flights)79May 2025: 75% on-time (321 flights)75June 2025: 69% on-time (316 flights)69Jun 2025July 2025: 65% on-time (324 flights)65August 2025: 75% on-time (305 flights)75September 2025: 90% on-time (292 flights)90Sep 2025October 2025: 80% on-time (304 flights)80November 2025: 80% on-time (288 flights)80December 2025: 72% on-time (290 flights)72Dec 2025January 2026: 83% on-time (278 flights)83February 2026: 78% on-time (261 flights)78March 2026: 71% on-time (289 flights)71Mar 2026April 2026: 83% on-time (291 flights)83May 2026: 64% on-time (297 flights)64

Best time to fly from ATL to MDW

Aim for departures around 6 a.m. (95% on-time); avoid 7 p.m. departures (60%).

On-time percentage by scheduled departure hour, ATL to MDW5 a.m.: 88% on-time (25 flights)56 a.m.: 95% on-time (365 flights)67 a.m.: 87% on-time (231 flights)78 a.m.: 88% on-time (842 flights)89 a.m.: 86% on-time (351 flights)910 a.m.: 84% on-time (328 flights)1011 a.m.: 84% on-time (734 flights)1112 p.m.: 82% on-time (250 flights)121 p.m.: 81% on-time (293 flights)132 p.m.: 76% on-time (455 flights)143 p.m.: 81% on-time (517 flights)154 p.m.: 73% on-time (392 flights)165 p.m.: 72% on-time (519 flights)176 p.m.: 73% on-time (306 flights)187 p.m.: 60% on-time (237 flights)198 p.m.: 72% on-time (499 flights)209 p.m.: 67% on-time (639 flights)2110 p.m.: 62% on-time (322 flights)22scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday76%19 min
Tuesday81%14 min
Wednesdaybest84%9 min
Thursday77%16 min
Friday76%18 min
Saturday80%13 min
Sunday74%17 min

What causes delays on this route

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

  • Late-arriving aircraft46%
  • Airline operations36%
  • National airspace system14%
  • Weather4%

Frequently asked questions

How often are flights from ATL to MDW delayed?
22% of ATL–MDW 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 15 minutes.
Which airline is most reliable from ATL to MDW?
Delta Air Lines has the best on-time record on this route at 82%, based on 2,983 flights. 3 airlines flew ATL–MDW frequently enough to compare in this period.
What is the best time of day to fly from ATL to MDW?
Departures around 6 a.m. have the best record (95% on-time), while departures around 7 p.m. have the worst (60%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from ATL to MDW?
The scheduled ATL–MDW flight time averages 1h 56m over 591 miles. Actual arrival times vary — flights on this route land 15+ minutes late 22% of the time.
How often are ATL to MDW flights cancelled?
1.3% 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 ATL to MDW?
May 2026 was the roughest month in this dataset, with only 64% of arrivals on time. The best was September 2025 at 90%. If your dates are flexible, that 26-point gap is worth planning around.

Based on 7,309 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.