Route profile
ATL→MDW
Flight reliability, delays and best times to fly from Atlanta to Chicago, 591 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 43% of comparable major US routes (4,598 compared)
Calculated from 11,363 flights. How this is calculated
ATL → MDW arrives on time 78.1% of the time; the return trip, MDW → ATL, arrives on time 80.4% of the time, a 2.3-point gap between the two directions of the same city pair.
ATL → MDW spends 21.0 minutes on the ground on a 591-mile trip: 15.1 minutes from pushback to wheels-up at ATL and 5.9 minutes from touchdown to gate at MDW.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
The airline matters unusually much on this route, a wider carrier-to-carrier gap than 93% of 2,692 comparable routes.
Delta Air Lines arrived on time 82.9% of the time, against 63.1% for Frontier Airlines, flying the exact same route.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 2,692 in the comparison.
Why ATL → MDW flights are cancelled
July 2023 – July 2026
ATL → MDW cancelled 160 of 11,363 scheduled flights — about 1 in every 71. The reason filed most often was extreme weather, 55.0% of the cancellations coded on this route — about 1 in every 129 scheduled flights.
Share of cancellations
Of 160 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
88 cancellations, 55.0% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
68 cancellations, 42.5% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
4 cancellations, 2.5% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
160 coded cancellations were recorded on ATL → MDW; the section appears from 50.
When it goes wrong
July 2023 – July 2026
46 min late
against a median of 4 min early
Percentiles over 11,363 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at MDW after arriving from ATL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 39% | Likely to miss |
| 45 min | 21% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 7.5% | Some risk |
| 120 min | 4.5% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.41% of the time and diverts 0.49% of the time, which a late arrival never shows up in.
Chance of missing is the share of 11,147 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 46 minutes late (90th-percentile gate arrival delay), over 11,363 operations.
Any other layover length: connection checker.
Best time to fly
ATL → MDW flights departing 5–9 AM arrived on time 89.1% of the time, against 66.1% for 9 PM–5 AM departures, a gap of 23.0 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 95.1% on time from 545 flights
- 7 AM: 88.9% on time from 374 flights
- 8 AM: 86.6% on time from 1,249 flights
- 9 AM: 88.0% on time from 695 flights
- 10 AM: 82.2% on time from 511 flights
- 11 AM: 85.2% on time from 1,086 flights
- 12 PM: 80.2% on time from 368 flights
- 1 PM: 77.6% on time from 472 flights
- 2 PM: 75.7% on time from 692 flights
- 3 PM: 79.6% on time from 836 flights
- 4 PM: 74.2% on time from 604 flights
- 5 PM: 71.2% on time from 716 flights
- 6 PM: 72.4% on time from 425 flights
- 7 PM: 56.6% on time from 395 flights
- 8 PM: 72.1% on time from 823 flights
- 9 PM: 70.3% on time from 1,000 flights
- 10 PM: 58.9% on time from 514 flights
- 11 PM: too few flights to score
Why ATL → MDW runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for ATL → MDW. Only delays of 15 minutes or more are attributed.
Late-arriving aircraft is the largest cause on ATL → MDW, at 47.3%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 89.1% of the time and 9 PM–5 AM departures 66.1%.
How this route holds up in bad weather
July 2023 – July 2026
The harder-hit end is MDW, where the flight lands. Its figure counts departures from MDW, so it says more about how that airport copes than about this route. Bad weather cancels 6.5 times the normal rate at MDW against 3.3 times at ATL. Cancelled in bad weather against normal hours: ATL 3.4% against 1.0%, MDW 5.0% against 0.8%. Flights that did leave MDW in bad weather arrived on time 62.3% of the time, against 78.1% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | ATL | MDW |
|---|---|---|
| Cancelled in bad weather | 3.4% | 5.0% |
| Cancelled in normal hours | 1.0% | 0.8% |
| Arrived on time, bad weather | 66.5% | 62.3% |
| Arrived on time, normal hours | 80.2% | 78.1% |
| Departures in bad weather | 105,854 | 26,598 |
Of the carriers on this route, Southwest Airlines (2.1% cancelled against 3.1% for the other carriers at ATL) cancelled the fewest departures from ATL in bad weather and Frontier Airlines (5.0% cancelled against 3.8% for the other carriers at ATL) the most.
This route’s airlines in bad weather at ATL
All departures from ATL| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| Southwest Airlines | 8,953 | 2.1%below the others | 3.1% |
| Delta Air Lines | 73,919 | 3.5%about level | 3.6% |
| Frontier Airlines | 4,928 | 5.0%above the others | 3.8% |
These are airport figures, not route figures: every scheduled departure from ATL and MDW, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from ATL on every route.
Weather source and limits. In full: ATL (airlines), MDW, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Southwest Airlines | 5,225 | 78.7% | 1.09% | -2 min | 6.5% |
| Delta Air Lines | 4,473 | 82.9% | 1.45% | -7 min | 5.5% |
| Frontier Airlines | 1,665 | 63.1% | 2.28% | 2 min | 16.8% |
Southwest Airlines flew 46.0% of the 11,363 flights listed. Frontier Airlines cancelled 2.28% of its flights here against 1.09% for Southwest Airlines.
Delta Air Lines arrived on time 19.8 percentage points more often than Frontier Airlines on this route.
Other ways to fly Atlanta to Chicago
Airport pairs in the same two city markets, as the DOT defines them.
| Route | Flights | On time | Cancelled | Median delay | Score |
|---|---|---|---|---|---|
| ATL→ORD Atlanta to Chicago | 18,588 | 74.1% | 1.68% | -3 min | 53 |
| ATL→MDW this route Atlanta to Chicago | 11,363 | 78.1% | 1.41% | -4 min | 63 |
ATL → MDW is the most reliable pairing for this journey at 78.1% on time, against 74.1% for ATL → ORD.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Sunday the least, a gap of 9.3 percentage points.
By month
- Jan: 79.9%
- Feb: 83.8%
- Mar: 80.1%
- Apr: 81.0%
- May: 69.6%
- Jun: 73.0%
- Jul: 65.9%
- Aug: 77.6%
- Sep: 85.3%
- Oct: 83.7%
- Nov: 83.0%
- Dec: 79.7%
July is historically the weakest month and September the strongest, a spread of 19.4 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 61.5% from 322 flights
- August 2023: 71.4% from 339 flights
- September 2023: 80.3% from 310 flights
- October 2023: 83.6% from 355 flights
- November 2023: 84.7% from 308 flights
- December 2023: 86.6% from 299 flights
- January 2024: 77.4% from 267 flights
- February 2024: 90.9% from 243 flights
- March 2024: 83.7% from 308 flights
- April 2024: 79.5% from 333 flights
- May 2024: 68.7% from 339 flights
- June 2024: 79.6% from 331 flights
- July 2024: 70.6% from 339 flights
- August 2024: 85.3% from 348 flights
- September 2024: 85.5% from 330 flights
- October 2024: 87.4% from 342 flights
- November 2024: 82.6% from 330 flights
- December 2024: 80.2% from 304 flights
- January 2025: 79.6% from 279 flights
- February 2025: 82.4% from 246 flights
- March 2025: 83.3% from 303 flights
- April 2025: 79.5% from 301 flights
- May 2025: 75.3% from 321 flights
- June 2025: 68.7% from 316 flights
- July 2025: 65.8% from 324 flights
- August 2025: 75.4% from 305 flights
- September 2025: 90.4% from 292 flights
- October 2025: 79.6% from 304 flights
- November 2025: 81.5% from 288 flights
- December 2025: 72.1% from 290 flights
- January 2026: 82.5% from 278 flights
- February 2026: 78.3% from 261 flights
- March 2026: 72.6% from 289 flights
- April 2026: 84.5% from 291 flights
- May 2026: 64.4% from 297 flights
- June 2026: 70.0% from 308 flights
- July 2026: 65.6% from 323 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 76.2% against 79.7% in the 12 months before — declining by 3.5 percentage points.
Data and methodology
Calculated by FlyerIntel from 11,363 ATL → MDW flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed