Carrier route record

MQORD→BUF

Envoy Air · Chicago to Buffalo

Flights: 422
Period: July 2025 to June 2026
Share of route: 19%
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 BUF lands a B, 2 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 422 flights. The strongest carrier on the route with a full sample, United Airlines, flew 612 at 73.8% on time.

The US average over the same twelve months is 77.6%, so there is little to separate Envoy on ORD to BUF from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

79.8%

Arrivals under 15 minutes late, of 410 completed flights

Avg delay

60 min

Across delayed arrivals only, not all flights

Cancelled

2.61%

National rate is 1.81%

Whole route

70.6%

Every carrier on ORD to BUF, 2,195 flights

These figures cover 422 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 BUF

Envoy flew 422 of the 2,195 flights on ORD to BUF, about 19% of it. Its 79.8% on time is 9 points better than the route as a whole, which runs 70.6%. Ranked by on-time rate it is first of five carriers on the route, where the range runs from Envoy at 79.8% to American at 58.8%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. United Airlines arrives on time 73.8% of the time; American Airlines manages 58.8%. Sample sizes sit next to every figure, because a two-point gap across 476 flights means less than a ten-point one.

On-time performance by carrier on ORD to BUF
Airline	Flights	On time	Avg delay	Cancelled	Grade
Envoy Air (this page)	422	79.8%	60 min	2.61%	B
Republic Airwaysthin sample	355	74.3%	74 min	5.07%	C−
United Airlines	612	73.8%	81 min	1.14%	C
SkyWest Airlinesthin sample	330	66.1%	84 min	4.85%	C−
American Airlines	476	58.8%	88 min	1.26%	D

The spread between United and American is 15 points, wide enough that it should decide the booking. On a hundred trips that is 15 more arrivals inside the on-time window.

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 11 points, against 15 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am43 flights86.0%
8am–11am143 flights84.3%
11am–2pm121 flights76.7%
2pm–5pm115 flights74.8%
5pm–8pm—
8pm–5am—

Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 86.0% of the time, against 74.8% for the afternoon window. That is 11 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 143 flights scheduled in it.

Across the year

Envoy on ORD to BUF through the year

Jul–Sep 2025131 flights79.7%
Oct–Dec 2025176 flights83.6%
Jan–Mar 2026109 flights75.2%
Apr–Jun 20266 flights—

Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 79.8% on time across 422 flights.

Quarter by quarter Envoy on ORD to BUF held fairly steady: 79.7% in Jul–Sep 2025, 83.6% in Oct–Dec 2025 and 75.2% in Jan–Mar 2026. A spread of 8 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Across the week, Tuesday is the strongest day at 87.9% on time and Sunday the weakest at 73.2%. 15 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Envoy 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 4,936 reported delay minutes.

Late-arriving aircraft
40%
National Airspace System
32%
Carrier
19%
Extreme weather
9%

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 4,936 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. The split is drawn from 4,936 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 86.0% on time here.

Cancellations run at 2.61%, against 1.81% nationally. That is about one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and stage length

What a delay here costs

7.1% 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 about an hour, which a normal layover absorbs.

At 474 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 is a different operation and performs like one: it runs 70.8% on time across 423 flights, 9 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 9 points of difference.

One caution: this is a thin sample. 422 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 BUF

Put together: treat all of this as provisional. 422 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 79.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 410 completed flights over 12 months sit behind that.

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.

Key figures