Route profile
ATL→ORD
Flight reliability, delays and best times to fly from Atlanta to Chicago, 606 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 19% of comparable major US routes (4,598 compared)
Calculated from 18,588 flights. How this is calculated
ATL → ORD arrives on time 74.1% of the time; the return trip, ORD → ATL, arrives on time 75.6% of the time.
ATL → ORD spends 34.7 minutes on the ground on a 606-mile trip: 19.1 minutes from pushback to wheels-up at ATL and 15.7 minutes from touchdown to gate at ORD.
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 91% of 2,692 comparable routes.
United Airlines arrived on time 79.6% of the time, against 61.4% 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 → ORD flights are cancelled
July 2023 – July 2026
ATL → ORD cancelled 313 of 18,588 scheduled flights — about 1 in every 59. The reason filed most often was extreme weather, 50.5% of the cancellations coded on this route — about 1 in every 118 scheduled flights.
Share of cancellations
Of 313 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.
158 cancellations, 50.5% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
126 cancellations, 40.3% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
29 cancellations, 9.3% 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.
313 coded cancellations were recorded on ATL → ORD; the section appears from 50.
When it goes wrong
July 2023 – July 2026
56 min late
against a median of 3 min early
Percentiles over 18,588 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at ORD after arriving from ATL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 44% | Likely to miss |
| 45 min | 25% | High risk |
| 60 min | 17% | High risk |
| 90 min | 9.4% | Some risk |
| 120 min | 6.1% | Some 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 1.68% of the time and diverts 0.35% of the time, which a late arrival never shows up in.
Chance of missing is the share of 18,210 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 56 minutes late (90th-percentile gate arrival delay), over 18,588 operations.
Any other layover length: connection checker.
Best time to fly
ATL → ORD flights departing 5–9 AM arrived on time 85.6% of the time, against 62.0% for 6–9 PM departures, a gap of 23.6 percentage points.
By day and hour
On-time arrival rate for each weekday and scheduled departure hour, in local time at the departure airport (ATL).
Hour of departure matters more than day of the week: hourly averages sit a typical 10.2 points from the route-wide rate, weekday averages 2.4 points.
| Hour | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Sunday |
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On-time rate, % · stronger color, fewer on time
- 40–49
- 50–59
- 60–69
- 70–79
- 80–89
- 90–99
- Fewer than 120 flights, not scored
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.
No slot is named best or worst: too few reach 500 flights. Departures before 6 AM and after 11 PM (173 flights) are not drawn: no slot in those hours has enough flights to score.
View as tableHide table
| Hour | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Sunday |
|---|---|---|---|---|---|---|---|
| 6 AM–7 AM | 84.0% on time250 flights | 91.9% on time211 flights | 88.7% on time233 flights | 84.5% on time223 flights | 79.4% on time236 flights | 85.9% on time236 flights | 86.1% on time243 flights |
| 7 AM–8 AM | 89.2% on time251 flights | 87.1% on time253 flights | 88.1% on time245 flights | 87.3% on time253 flights | 86.0% on time257 flights | 85.6% on time186 flights | 88.2% on time234 flights |
| 8 AM–9 AM | 69 flights, too few to score | 78 flights, too few to score | 78 flights, too few to score | 78 flights, too few to score | 67 flights, too few to score | 85 flights, too few to score | 78 flights, too few to score |
| 9 AM–10 AM | 73.3% on time132 flights | 99 flights, too few to score | 102 flights, too few to score | 86.8% on time121 flights | 76.6% on time131 flights | 115 flights, too few to score | 118 flights, too few to score |
| 10 AM–11 AM | 86.9% on time216 flights | 84.4% on time213 flights | 86.9% on time215 flights | 82.0% on time217 flights | 80.9% on time213 flights | 73.3% on time213 flights | 77.0% on time216 flights |
| 11 AM–12 PM | 86.7% on time203 flights | 83.5% on time184 flights | 87.6% on time194 flights | 84.5% on time215 flights | 83.6% on time205 flights | 81.2% on time151 flights | 81.5% on time202 flights |
| 12 PM–1 PM | 73.2% on time124 flights | 81.9% on time144 flights | 81.7% on time132 flights | 80.5% on time134 flights | 77.8% on time129 flights | 115 flights, too few to score | 73.9% on time121 flights |
| 1 PM–2 PM | 76.5% on time167 flights | 82.2% on time164 flights | 85.5% on time167 flights | 78.8% on time160 flights | 76.4% on time170 flights | 109 flights, too few to score | 73.9% on time135 flights |
| 2 PM–3 PM | 33 flights, too few to score | 29 flights, too few to score | 30 flights, too few to score | 23 flights, too few to score | 30 flights, too few to score | 32 flights, too few to score | 31 flights, too few to score |
| 3 PM–4 PM | 73.2% on time335 flights | 69.6% on time361 flights | 72.3% on time358 flights | 69.0% on time313 flights | 66.0% on time331 flights | 73.2% on time329 flights | 70.3% on time318 flights |
| 4 PM–5 PM | 65 flights, too few to score | 56 flights, too few to score | 71 flights, too few to score | 56 flights, too few to score | 57 flights, too few to score | 49 flights, too few to score | 46 flights, too few to score |
| 5 PM–6 PM | 54.0% on time181 flights | 59.8% on time171 flights | 63.3% on time173 flights | 47.7% on time177 flights | 48.6% on time184 flights | 58.3% on time129 flights | 41.8% on time176 flights |
| 6 PM–7 PM | 67.4% on time223 flights | 74.7% on time223 flights | 69.4% on time222 flights | 62.7% on time233 flights | 57.5% on time237 flights | 63.0% on time215 flights | 60.2% on time241 flights |
| 7 PM–8 PM | 59.4% on time160 flights | 119 flights, too few to score | 59.8% on time135 flights | 52.4% on time153 flights | 63.8% on time157 flights | 114 flights, too few to score | 60.4% on time155 flights |
| 8 PM–9 PM | 57.4% on time130 flights | 75 flights, too few to score | 94 flights, too few to score | 54.1% on time137 flights | 61.9% on time132 flights | 38 flights, too few to score | 56.8% on time126 flights |
| 9 PM–10 PM | 42 flights, too few to score | 36 flights, too few to score | 31 flights, too few to score | 50 flights, too few to score | 42 flights, too few to score | 42 flights, too few to score | 50 flights, too few to score |
| 10 PM–11 PM | 68.5% on time181 flights | 77.5% on time130 flights | 76.5% on time137 flights | 65.5% on time181 flights | 68.9% on time187 flights | 77.1% on time159 flights | 72.5% on time194 flights |
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 84.2% on time from 138 flights
- 6 AM: 85.7% on time from 1,632 flights
- 7 AM: 87.4% on time from 1,679 flights
- 8 AM: 79.8% on time from 533 flights
- 9 AM: 78.1% on time from 818 flights
- 10 AM: 81.6% on time from 1,503 flights
- 11 AM: 84.2% on time from 1,354 flights
- 12 PM: 77.6% on time from 899 flights
- 1 PM: 78.8% on time from 1,072 flights
- 2 PM: 69.6% on time from 208 flights
- 3 PM: 70.5% on time from 2,345 flights
- 4 PM: 64.9% on time from 400 flights
- 5 PM: 53.1% on time from 1,191 flights
- 6 PM: 64.8% on time from 1,594 flights
- 7 PM: 60.4% on time from 993 flights
- 8 PM: 57.9% on time from 732 flights
- 9 PM: 66.7% on time from 293 flights
- 10 PM: 71.9% on time from 1,169 flights
- 11 PM: too few flights to score
Why ATL → ORD runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
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 → ORD. Only delays of 15 minutes or more are attributed.
How this route holds up in bad weather
July 2023 – July 2026
The harder-hit end is ORD, where the flight lands. Its figure counts departures from ORD, so it says more about how that airport copes than about this route. Bad weather cancels 5.5 times the normal rate at ORD against 3.3 times at ATL. Cancelled in bad weather against normal hours: ATL 3.4% against 1.0%, ORD 6.5% against 1.2%. Flights that did leave ORD in bad weather arrived on time 55.7% of the time, against 77.1% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | ATL | ORD |
|---|---|---|
| Cancelled in bad weather | 3.4% | 6.5% |
| Cancelled in normal hours | 1.0% | 1.2% |
| Arrived on time, bad weather | 66.5% | 55.7% |
| Arrived on time, normal hours | 80.2% | 77.1% |
| Departures in bad weather | 105,854 | 104,455 |
Of the carriers on this route, American Airlines (2.4% cancelled against 3.4% 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. One more carrier flies this route but has too few bad-weather departures from ATL to compare.
This route’s airlines in bad weather at ATL
All departures from ATL| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| American Airlines | 2,658 | 2.4%below the others | 3.4% |
| United Airlines | 2,567 | 2.6%below the others | 3.6% |
| Delta Air Lines | 73,919 | 3.5%about level | 3.6% |
| Republic Airways | 598 | 4.2%about level | 3.9% |
| Spirit Airlines | 2,965 | 3.9%above the others | 3.2% |
| Frontier Airlines | 4,928 | 5.0%above the others | 3.8% |
These are airport figures, not route figures: every scheduled departure from ATL and ORD, 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), ORD, 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 |
|---|---|---|---|---|---|
| Delta Air Lines | 7,714 | 72.9% | 1.39% | 0 min | 8.1% |
| United Airlines | 4,914 | 79.6% | 1.24% | -5 min | 7.9% |
| American Airlines | 1,921 | 75.6% | 2.08% | -9 min | 11.3% |
| Frontier Airlines | 1,677 | 61.4% | 3.10% | 3 min | 17.9% |
| Envoy Air | 1,066 | 75.0% | 1.97% | -4 min | 8.6% |
| Spirit Airlines | 702 | 69.3% | 1.42% | -4 min | 12.3% |
| Republic Airways | 536 | 76.7% | 3.73% | -6 min | 9.1% |
Delta Air Lines flew 41.6% of the 18,530 flights listed. Republic Airways cancelled 3.73% of its flights here against 1.24% for United Airlines.
United Airlines arrived on time 18.2 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 this route Atlanta to Chicago | 18,588 | 74.1% | 1.68% | -3 min | 53 |
| ATL→MDW 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.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| DL1147 Delta Air Lines | 9:00 AM | 1,054 | 80.4% |
| DL2738 Delta Air Lines | 3:40 PM | 1,028 | 68.7% |
| UA516 United Airlines | 3:30 PM | 989 | 78.3% |
| DL1477 Delta Air Lines | 1:25 PM | 977 | 72.4% |
| UA1046 United Airlines | 6:59 PM | 939 | 68.2% |
| DL2879 Delta Air Lines | 5:25 PM | 887 | 54.7% |
| DL1199 Delta Air Lines | 10:55 PM | 732 | 73.9% |
DL1147 (9:00 AM) arrived on time 80.4% of the time, 25.7 points more often than DL2879 (5:25 PM) at 54.7%.
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Friday the least, a gap of 6.9 percentage points.
By month
- Jan: 75.0%
- Feb: 80.0%
- Mar: 72.4%
- Apr: 73.2%
- May: 72.1%
- Jun: 68.4%
- Jul: 63.4%
- Aug: 72.0%
- Sep: 83.2%
- Oct: 81.9%
- Nov: 78.5%
- Dec: 74.6%
July is historically the weakest month and September the strongest, a spread of 19.8 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 60.2% from 534 flights
- August 2023: 67.6% from 533 flights
- September 2023: 82.8% from 516 flights
- October 2023: 83.5% from 514 flights
- November 2023: 86.2% from 443 flights
- December 2023: 87.7% from 447 flights
- January 2024: 77.2% from 425 flights
- February 2024: 86.2% from 400 flights
- March 2024: 80.7% from 461 flights
- April 2024: 78.7% from 469 flights
- May 2024: 65.8% from 490 flights
- June 2024: 68.9% from 486 flights
- July 2024: 57.2% from 501 flights
- August 2024: 69.1% from 512 flights
- September 2024: 82.2% from 496 flights
- October 2024: 87.1% from 515 flights
- November 2024: 83.5% from 473 flights
- December 2024: 76.4% from 440 flights
- January 2025: 79.7% from 431 flights
- February 2025: 78.8% from 391 flights
- March 2025: 78.4% from 476 flights
- April 2025: 74.3% from 500 flights
- May 2025: 76.9% from 557 flights
- June 2025: 67.8% from 568 flights
- July 2025: 66.8% from 570 flights
- August 2025: 78.5% from 573 flights
- September 2025: 84.4% from 541 flights
- October 2025: 75.8% from 569 flights
- November 2025: 67.0% from 526 flights
- December 2025: 60.5% from 487 flights
- January 2026: 68.5% from 445 flights
- February 2026: 75.5% from 445 flights
- March 2026: 58.5% from 516 flights
- April 2026: 67.4% from 554 flights
- May 2026: 72.7% from 596 flights
- June 2026: 68.4% from 584 flights
- July 2026: 68.0% from 604 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 70.6% against 76.4% in the 12 months before — declining by 5.8 percentage points.
Data and methodology
Calculated by FlyerIntel from 18,588 ATL → ORD 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