Carrier route record
UABZN→ORD
United Airlines · Bozeman to Chicago
- Flights
- 720
- Period
- September 2025 to August 2026
- Share of route
- 58%
- Carriers
- 4
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on BZN to ORD lands a B+, level with the national rate of 77.3%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 720 flights, with a median arrival 6 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate United on BZN to ORD from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
77.6%
Arrivals under 15 minutes late, of 709 completed flights
Avg delay
91 min
Across delayed arrivals only, not all flights
Cancelled
0.97%
National rate is 1.89%
Whole route
73.2%
Every carrier on BZN to ORD, 1,251 flights
These figures cover 720 flights between September 2025 and August 2026. Beyond the headline rate, 10.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
United against every carrier on BZN to ORD
United flew 720 of the 1,251 flights on BZN to ORD, most of the route. Its 77.6% on time is 4 points better than the route as a whole, which runs 73.2%. Ranked by on-time rate it is first of four carriers on the route, where the range runs from United at 77.6% to American at 66.4%. 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 |
|---|---|---|---|---|---|
| United Airlines (this page) | 720 | 77.6% | 91 min | 0.97% | B+ |
| Envoy Airthin sample | 41 | 75.6% | 71 min | 0.00% | B+ |
| SkyWest Airlinesthin sample | 46 | 69.6% | 53 min | 0.00% | C+ |
| American Airlines | 444 | 66.4% | 89 min | 0.90% | C+ |
Flight by flight
United flight numbers on BZN to ORD
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 points, against half a point between the best and worst carrier.
- 5am–8am19 flights—
- 8am–11am215 flights88.5%
- 11am–2pm365 flights76.7%
- 2pm–5pm121 flights59.2%
- 5pm–8pm—
- 8pm–5am—
Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 88.5% of the time, against 59.2% for the afternoon window. That is 29 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 365 flights scheduled in it.
Across the year
United on BZN to ORD through the year
October is the best month on the calendar at 92.9% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. August was the busiest month here, with 93 flights.
Across the week, Tuesday is the strongest day at 84.7% on time and Sunday the weakest at 68.9%, a spread of 16 points.
Arrival by arrival
How late United on BZN to ORD runs when it is late
United on BZN to ORD often beats the schedule: 233 of 709 completed flights, 33%, arrived 15 minutes or more early. The 159 late arrivals split 43 under half an hour, 40 between 30 and 60 minutes, and 76 an hour or more.
- 15+ min early233 flights32.9%
- Within 15 min317 flights44.7%
- 15–29 min late43 flights6.1%
- 30–59 min late40 flights5.6%
- 1–2 hours late34 flights4.8%
- 2+ hours late42 flights5.9%
Scale runs 0% to 100%.
Share of 709 completed flights by arrival against schedule.
34 of 145 late departures made up the time and arrived on time, 23% of them. In the other direction, 48 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at ORD.
The worst days
Worst days for United on BZN to ORD
The latest arrival of the period was on 11 June 2026, 18 hours 39 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). On three of the five worst days the largest share was filed as national airspace system delay.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 11 June 2026 | 18 hours 39 minutes | Carrier |
| 27 July 2026 | 7 hours 46 minutes | National Airspace System |
| 6 March 2026 | 5 hours 39 minutes | National Airspace System |
| 15 March 2026 | 5 hours 29 minutes | National Airspace System |
| 5 August 2026 | 5 hours 24 minutes | Carrier |
Delay causes
Why United runs late on this route
National Airspace System accounts for 56% of the 15,000 delay minutes carriers reported here, and the remaining four split what is left.
- 56%National Airspace System
- 24%Late-arriving aircraft
- 19%Carrier
- 0%Extreme weather
56% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 8,135 minutes out of 15,000, against a national NAS share of 21%. The split is drawn from 14,532 reported delay minutes.
Cancellations sit at 0.97% against a national 1.89%, which is ordinary. Diversions add another 0.56%.
Connections and stage length
What a delay here costs
10.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection 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.
The return leg is a different operation and performs like one: it runs 71.6% on time across 720 flights, 6 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 6 points of difference.
One caution: this is a thin sample. 720 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 United on BZN to ORD
Put together: treat all of this as provisional. 720 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 77.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 709 completed flights over 12 months sit behind that.
Related
Where to go next
- BZN to ORD, every carrier
- United on ORD to BZN, the return leg
- American Airlines on BZN to ORD66.4%
- United Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- Flying to ski country: which routes into the mountains run on time
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.