Carrier route record

OOBUF→ORD

SkyWest Airlines · Buffalo to Chicago

Flights: 330
Period: July 2025 to June 2026
Share of route: 15%
Carriers: 5

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.

SkyWest on BUF to ORD draws a D−. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is about 2.2 hours behind schedule. Build slack into anything you connect to. That rests on 330 flights. The strongest carrier on the route with a full sample, American Airlines, flew 476 at 84.0% on time.

American Airlines is the most reliable of the three carriers covered here at 84.0% on time across 476 flights.

On time

60.2%

Arrivals under 15 minutes late, of 309 completed flights

Avg delay

134 min

Across delayed arrivals only, not all flights

Cancelled

6.06%

National rate is 1.81%

Whole route

74.0%

Every carrier on BUF to ORD, 2,196 flights

These figures cover 330 flights between July 2025 and June 2026. Beyond the headline rate, 20.1% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Carrier by carrier

SkyWest against every carrier on BUF to ORD

SkyWest flew 330 of the 2,196 flights on BUF to ORD, about 15% of it. Its 60.2% on time is 14 points worse than the route as a whole, which runs 74.0%. Ranked by on-time rate it is last of five carriers on the route, where the range runs from American at 84.0% to SkyWest at 60.2%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. American Airlines arrives on time 84.0% of the time; Envoy Air manages 70.8%. Sample sizes sit next to every figure, because a two-point gap across 423 flights means less than a ten-point one.

On-time performance by carrier on BUF to ORD
Airline	Flights	On time	Avg delay	Cancelled	Grade
American Airlines	476	84.0%	124 min	1.47%	B
Republic Airwaysthin sample	355	76.2%	95 min	3.66%	B−
United Airlines	612	74.1%	88 min	1.47%	C
Envoy Air	423	70.8%	68 min	3.31%	C−
SkyWest Airlines (this page)thin sample	330	60.2%	134 min	6.06%	D−

Envoy Air cancels 3.3% 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 SkyWest runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 40 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am15 flights—
8am–11am81 flights87.0%
11am–2pm7 flights—
2pm–5pm57 flights47.1%
5pm–8pm170 flights51.6%
8pm–5am—

Scale runs 40% to 90%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 87.0% of the time, against 47.1% for the afternoon window. That is 40 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 170 flights scheduled in it.

Across the year

SkyWest on BUF to ORD through the year

Jul–Sep 202516 flights—
Oct–Dec 2025122 flights61.9%
Jan–Mar 202689 flights36.6%
Apr–Jun 2026103 flights76.5%

Scale runs 30% to 80%. 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 60.2% on time across 330 flights.

SkyWest on BUF to ORD did not run the same all year. Its best quarter was Apr–Jun 2026 at 76.5% on time and its weakest Jan–Mar 2026 at 36.6%, a swing of 40 points on roughly 110 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Thursday is the strongest day at 70.7% on time and Sunday the weakest at 44.4%. 26 points is a smaller lever than departure hour, but it is free.

Delay causes

Why SkyWest 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 16,000 reported delay minutes.

Late-arriving aircraft
38%
Carrier
33%
National Airspace System
25%
Extreme weather
4%

38% 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 16,000 reported delay minutes here, that single category outweighs weather by 9 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 16,494 reported delay minutes.

The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 87.0% on time here.

Cancellations run at 6.06%, against 1.81% nationally. That is roughly one flight in fifteen 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

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 20.1% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

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 8am–11am window matters as much as it does.

The return leg is a different operation and performs like one: it runs 66.1% on time across 330 flights, 6 points above 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. 330 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 SkyWest on BUF to ORD

Put together: the delay figures matter less here than the 6.06% cancellation rate. A late arrival costs you about 2.2 hours; a cancelled flight costs you the day. Book the 8am–11am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 309 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