Carrier route record
AAORD→BZN
American Airlines · Chicago to Bozeman
- Flights
- 468
- Period
- July 2025 to June 2026
- Share of route
- 37%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with American Airlines.
American on ORD to BZN draws a D+. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 468 flights, with a median arrival 3 minutes late.
The national on-time rate over the same period is 77.6%, so American on ORD to BZN runs 14 points behind the country as a whole. Across a thousand flights that is about 136 extra late arrivals.
Key figures
On time
64.0%
Arrivals under 15 minutes late, of 464 completed flights
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
0.43%
National rate is 1.81%
Whole route
67.4%
Every carrier on ORD to BZN, 1,256 flights
These figures cover 468 flights between July 2025 and June 2026. Beyond the headline rate, 15.1% 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 BZN
American flew 468 of the 1,256 flights on ORD to BZN, about 37% of it. Its 64.0% on time is 3 points worse than the route as a whole, which runs 67.4%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from SkyWest at 75.0% to Envoy at 55.0%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 89 | 75.0% | 63 min | 0.00% | B+ |
| United Airlines | 658 | 69.6% | 64 min | 1.06% | C |
| American Airlines (this page) | 468 | 64.0% | 64 min | 0.43% | D+ |
| Envoy Airthin sample | 41 | 55.0% | 31 min | 0.00% | D+ |
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 24 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am272 flights64.3%
- 11am–2pm131 flights72.5%
- 2pm–5pm—
- 5pm–8pm56 flights48.2%
- 8pm–5am9 flights—
Scale runs 40% to 80%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 48.2% on time, against 72.5% for the 11am–2pm 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 8am–11am window is the busiest, with 272 flights scheduled in it.
Across the year
American on ORD to BZN through the year
September is the best month on the calendar at 80.7% 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 61 flights.
Across the week, Tuesday is the strongest day at 78.6% on time and Sunday the weakest at 54.3%. 24 points is a smaller lever than departure hour, but it is free.
Delay causes
Why American runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 11,000 reported delay minutes.
- 40%Late-arriving aircraft
- 29%National Airspace System
- 25%Carrier
- 5%Extreme weather
40% 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 11,000 reported delay minutes here, that single category outweighs weather by 7 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 10,663 reported delay minutes.
Cancellations are rare at 0.43%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
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. 15.1% 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 1,185 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 runs 65.2% on time across 467 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 468 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 BZN
Put together: treat all of this as provisional. 468 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 64.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 464 completed flights over 12 months sit behind that.
Related
Where to go next
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.