Carrier route record
F9ORD→ATL
Frontier Airlines · Chicago to Atlanta
- Flights
- 713
- 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 Frontier Airlines.
Frontier 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 713 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
67.8%
Arrivals under 15 minutes late, of 689 completed flights
Avg delay
100 min
Across delayed arrivals only, not all flights
Cancelled
3.09%
National rate is 1.81%
Whole route
75.0%
Every carrier on ORD to ATL, 6,409 flights
These figures cover 713 flights between July 2025 and June 2026. Beyond the headline rate, 13.2% 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
Frontier against every carrier on ORD to ATL
Frontier flew 713 of the 6,409 flights on ORD to ATL, about 11% of it. Its 67.8% on time is 7 points worse than the route as a whole, which runs 75.0%. Ranked by on-time rate it is number six 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; American Airlines manages 65.3%. Sample sizes sit next to every figure, because a two-point gap across 689 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 (this page) | 713 | 67.8% | 100 min | 3.09% | C− |
| American Airlines | 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+ |
American Airlines cancels 3.0% 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.
Flight by flight
Frontier flight numbers on ORD to ATL
Departure window
When Frontier 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 15 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am293 flights73.6%
- 8am–11am31 flights80.0%
- 11am–2pm108 flights67.0%
- 2pm–5pm130 flights66.9%
- 5pm–8pm151 flights55.2%
- 8pm–5am—
Scale runs 45% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 55.2% on time, against 80.0% for the 8am–11am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5am–8am window is the busiest, with 293 flights scheduled in it.
Across the year
Frontier on ORD to ATL through the year
Delays peak in March, when the on-time rate falls to 45.6%. February is the strongest month at 88.2%. Moving a flexible trip across that boundary buys 43 points. October was the busiest month here, with 68 flights.
Across the week, Wednesday is the strongest day at 75.6% on time and Friday the weakest at 61.3%. 14 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Frontier runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 50% of the 22,000 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.
- 50%Late-arriving aircraft
- 25%National Airspace System
- 22%Carrier
- 3%Extreme weather
50% 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 22,000 reported delay minutes here, that single category outweighs weather by 16 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 22,084 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 80.0% on time here.
Cancellations run at 3.09%, against 1.81% nationally. That is about 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. 13.2% 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 62.8% on time across 711 flights, 5 points below 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 5 points of difference.
One caution: this is a thin sample. 713 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 Frontier on ORD to ATL
Put together: the delay figures matter less here than the 3.09% cancellation rate. A late arrival costs you an hour and a half; a cancelled flight costs you the day. Book the 8am–11am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 689 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to ATL, every carrier
- Frontier 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%
- American Airlines on ORD to ATL65.3%
- Frontier 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
- Same route, different airline: where the carrier you pick matters most
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.