MSO to ORD flight delays
Missoula, MT (MSO) Chicago, IL (ORD) · 1,332 miles
525 flights · January 2025 – August 2026 · US Bureau of Transportation Statistics
71.71%
Arrived on time
Within 15 minutes of schedule
0.95%
Cancelled
Share of scheduled flights
74 min
When late, late by
Average across delayed arrivals
22 min
Delay per flight
Averaged over every flight flown
What the record says about this route
The season swings this route hard. In May it ran 33.7 points more punctual than in March — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.
The route has been getting better. The later months in the record run 8.7 points more punctual than the earlier ones, which usually means a schedule that was too tight has been given more room.
This route does worse than its own airport. MSO as a whole runs 12.4 points more punctual than these flights, which points at something specific to the route — the time of day it is scheduled, or the aircraft that feed it — rather than the airport.
The two directions do not behave alike. ORD to MSO arrives on time 5.8 points more often than the outbound. Delay accumulates through the flying day, so whichever direction is scheduled later tends to carry the worse record — which is an argument for booking the morning departure if the choice exists.
Which airline should you fly on this route?
Over January 2025 – August 2026, Envoy Air arrived on time most often on MSO to ORD. United Airlines was late most often. Flights ran closest to schedule in May and worst in December.
Every airline on MSO to ORD
Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.
| Airline | Flights | On time | Cancelled | Avg delay | Grade |
|---|---|---|---|---|---|
| Envoy Air | 373 | 72.05% | 0.27% | 76 min | D |
| United Airlines | 104 | 71.13% | 2.88% | 66 min | D |
| SkyWest Airlines | 48 | 70.21% | 2.08% | 77 min | — |
Month by month
Share of flights that arrived within 15 minutes of schedule, by month flown.
The return leg
ORD to MSO Chicago back to Missoula 77.46% on time CCommon questions
Are flights from Missoula to Chicago usually delayed?
71.71% of flights on the MSO to ORD route arrived within 15 minutes of schedule, so roughly 3 in every ten arrived late. That is worse than the average route in this record.
Which airline is most on time from Missoula to Chicago?
Envoy Air, at 72.05% on time across 373 flights. The least punctual on the route was United Airlines at 71.13%.
How often are MSO to ORD flights cancelled?
0.95% of scheduled flights did not operate — about 10 in every thousand. That is in the normal range.
What is the best month to fly Missoula to Chicago?
May, when 95% of flights arrived on time. The worst was March at 61.3%.
When MSO to ORD flights are late, how late are they?
About 74 minutes on average across the flights that arrived more than 15 minutes behind schedule.
What these figures do and do not tell you
Everything on this page is counted from the flights that actually operated on MSO to ORD during January 2025 – August 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.
A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.
Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →