Carrier route record
MQORD→STL
Envoy Air · Chicago to St. Louis
- Flights
- 727
- Period
- July 2025 to June 2026
- Share of route
- 24%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Envoy Air.
Envoy on ORD to STL sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land roughly 50 minutes behind schedule. That rests on 727 flights. The strongest carrier on the route with a full sample, Republic Airways, flew 444 at 76.2% on time.
Republic Airways is the most reliable of the four carriers covered here at 76.2% on time across 444 flights.
Key figures
On time
75.0%
Arrivals under 15 minutes late, of 708 completed flights
Avg delay
52 min
Across delayed arrivals only, not all flights
Cancelled
2.34%
National rate is 1.81%
Whole route
71.0%
Every carrier on ORD to STL, 3,068 flights
These figures cover 727 flights between July 2025 and June 2026. The median arrival is 5 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Envoy against every carrier on ORD to STL
Envoy flew 727 of the 3,068 flights on ORD to STL, about 24% of it. Its 75.0% on time is 4 points better than the route as a whole, which runs 71.0%. Ranked by on-time rate it is number two of five carriers on the route, where the range runs from Republic at 76.2% to American at 65.6%.
The choice of carrier is not cosmetic here. Republic Airways arrives on time 76.2% of the time; American Airlines manages 65.6%. Sample sizes sit next to every figure, because a two-point gap across 535 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 444 | 76.2% | 77 min | 2.48% | B |
| Envoy Air (this page) | 727 | 75.0% | 52 min | 2.34% | B |
| United Airlines | 528 | 71.2% | 79 min | 1.33% | C |
| SkyWest Airlines | 834 | 68.2% | 73 min | 4.20% | C− |
| American Airlines | 535 | 65.6% | 86 min | 2.62% | C |
SkyWest Airlines cancels 4.2% 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.
Departure window
When Envoy runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 32 points, against 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am125 flights88.6%
- 8am–11am62 flights65.0%
- 11am–2pm223 flights79.3%
- 2pm–5pm156 flights78.8%
- 5pm–8pm122 flights59.3%
- 8pm–5am39 flights56.4%
Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 56.4% on time, against 88.6% for the 5am–8am 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 11am–2pm window is the busiest, with 223 flights scheduled in it.
Across the year
Envoy on ORD to STL through the year
January is the weak month at 62.5% on time, against 87.7% in May. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. March was the busiest month here, with 123 flights.
Across the week, Tuesday is the strongest day at 79.8% on time and Friday the weakest at 67.0%. 13 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Envoy runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 9,152 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.
- 48%Late-arriving aircraft
- 27%National Airspace System
- 13%Extreme weather
- 12%Carrier
Extreme weather accounts for 13% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.1 times the usual weather exposure. The split is drawn from 9,152 reported delay minutes.
48% 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 9,152 reported delay minutes here, that single category outweighs weather by 4 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.
Cancellations sit at 2.34% against a national 1.81%, which is ordinary. Diversions add another 0.28%.
Connections and stage length
What a delay here costs
7.3% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 50 minutes, which a normal layover absorbs.
At 258 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 74.6% on time across 728 flights, within half 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. 727 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 Envoy on ORD to STL
Put together: treat all of this as provisional. 727 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 75.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 708 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to STL, every carrier
- Envoy on STL to ORD, the return leg
- Republic Airways on ORD to STL76.2%
- United Airlines on ORD to STL71.2%
- SkyWest Airlines on ORD to STL68.2%
- American Airlines on ORD to STL65.6%
- Envoy Air network-wide record
- Chicago O'Hare International (ORD) delay statistics
- St. Louis Lambert International (STL) delay statistics
- Same route, different airline: where the carrier you pick matters most
- Why the first flight of the morning is statistically safest
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.