Best Time to Fly MSO to ORD: On-Time Stats by Hour & Airline
Missoula Montana → Chicago O'Hare International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 75.0% of Missoula (MSO) to Chicago (ORD) flights arrived on time (500 scheduled flights). That is 2.7 points below the national average of 77.6%.
Among 3 airlines, United Airlines led with 79.4% on time and SkyWest Airlines was last with 73.1%.
Over 24 months, Thursday was the most reliable day (85% on time) and March the worst month (61%).
The cancellation rate was 0.8% (US average 1.8%).
MSO to ORD on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 79.4% | 101 min | 2.9% | 104 |
| Envoy Air | 74.0% | 81 min | 0.0% | 343 |
| SkyWest Airlines | 73.1% | 77 min | 1.9% | 53 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly MSO to ORD
On-time arrival % by scheduled departure hour (local time), 806 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 90.2% | 0.0% | 51 |
| 6am–7am | 84.9% | 0.0% | 53 |
| 7am–8am | Limited data | 6 | |
| 8am–9am | Limited data | 10 | |
| 12pm–1pm | 72.6% | 0.9% | 460 |
| 1pm–2pm | 73.2% | 0.0% | 226 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on MSO to ORD
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Christmas & New Year (Dec 20 - Jan 3) | Limited data | 15 | ||
| Summer peak (Jun 15 - Aug 15) | 74.2% | -2.0 pts | 0.3% | 312 |
| All other days | 76.2% | — | 0.8% | 479 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).