Carrier route record
AAORD→ATL
American Airlines · Chicago to Atlanta
- Flights
- 689
- Period
- July 2025 to June 2026
- Share of route
- 11%
- Carriers
- 9
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with American Airlines.
American on ORD to ATL draws a C−. About one flight in three arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 689 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 2,623 at 80.4% on time.
Delta Air Lines is the most reliable of the four carriers covered here at 80.4% on time across 2,623 flights.
Key figures
On time
65.3%
Arrivals under 15 minutes late, of 666 completed flights
Avg delay
86 min
Across delayed arrivals only, not all flights
Cancelled
3.05%
National rate is 1.81%
Whole route
75.0%
Every carrier on ORD to ATL, 6,409 flights
These figures cover 689 flights between July 2025 and June 2026. Beyond the headline rate, 16.1% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
American against every carrier on ORD to ATL
American flew 689 of the 6,409 flights on ORD to ATL, about 11% of it. Its 65.3% on time is 10 points worse than the route as a whole, which runs 75.0%. Ranked by on-time rate it is number seven of nine carriers on the route, where the range runs from Delta at 80.4% to Spirit at 60.0%. Four of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 80.4% of the time; Frontier Airlines manages 67.8%. Sample sizes sit next to every figure, because a two-point gap across 713 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 2,623 | 80.4% | 87 min | 2.36% | B |
| PSA Airlinesthin sample | 5 | 80.0% | 58 min | 0.00% | B+ |
| Envoy Air | 366 | 77.7% | 62 min | 2.19% | B |
| United Airlines | 1,611 | 74.7% | 68 min | 1.12% | C |
| Republic Airwaysthin sample | 287 | 72.1% | 63 min | 4.53% | C− |
| Frontier Airlines | 713 | 67.8% | 100 min | 3.09% | C− |
| American Airlines (this page) | 689 | 65.3% | 86 min | 3.05% | C− |
| SkyWest Airlinesthin sample | 40 | 61.5% | 93 min | 2.50% | D |
| Spirit Airlinesthin sample | 75 | 60.0% | 74 min | 0.00% | D+ |
Frontier Airlines cancels 3.1% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Departure window
When American runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am112 flights79.2%
- 8am–11am66 flights76.9%
- 11am–2pm168 flights68.1%
- 2pm–5pm121 flights54.7%
- 5pm–8pm142 flights59.3%
- 8pm–5am80 flights57.1%
Scale runs 45% to 85%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 79.2% of the time, against 54.7% for the afternoon window. That is 25 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 168 flights scheduled in it.
Across the year
American on ORD to ATL through the year
September is the best month on the calendar at 87.2% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. July was the busiest month here, with 111 flights.
Across the week, Tuesday is the strongest day at 71.6% on time and Monday the weakest at 57.4%. 14 points is a smaller lever than departure hour, but it is free.
Delay causes
Why American runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 20,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 54%Late-arriving aircraft
- 30%Carrier
- 13%National Airspace System
- 2%Extreme weather
- 0%Security
54% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 20,000 reported delay minutes here, that single category outweighs weather by 24 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 19,872 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 79.2% on time here.
Cancellations run at 3.05%, against 1.81% nationally. That is roughly one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 16.1% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 606 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 72.2% on time across 688 flights, 7 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 7 points of difference.
One caution: this is a thin sample. 689 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking American on ORD to ATL
Put together: the delay figures matter less here than the 3.05% cancellation rate. A late arrival costs you an hour and a half; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 666 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to ATL, every carrier
- American on ATL to ORD, the return leg
- Delta Air Lines on ORD to ATL80.4%
- Envoy Air on ORD to ATL77.7%
- United Airlines on ORD to ATL74.7%
- Republic Airways on ORD to ATL72.1%
- Frontier Airlines on ORD to ATL67.8%
- American Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.