Carrier route record

OOORD→MKE

SkyWest Airlines · Chicago to Milwaukee

Flights: 4,933
Period: July 2025 to June 2026
Share of route: 95%
Carriers: 4

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

SkyWest on ORD to MKE carries a cancellation problem, not just a delay problem: 4.6% of scheduled flights never operate, against 1.8% nationally. Of the ones that do fly, about two flights in three arrive on time, worth a D− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 4,933 flights, with a median arrival 1 minute late.

The national on-time rate over the same period is 77.6%, so SkyWest on ORD to MKE runs 14 points behind the country as a whole. Across a thousand flights that is about 139 extra late arrivals.

On time

63.7%

Arrivals under 15 minutes late, of 4,698 completed flights

Avg delay

93 min

Across delayed arrivals only, not all flights

Cancelled

4.64%

National rate is 1.81%

Whole route

64.1%

Every carrier on ORD to MKE, 5,201 flights

These figures cover 4,933 flights between July 2025 and June 2026. Beyond the headline rate, 17.6% 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 ORD to MKE

SkyWest flew 4,933 of the 5,201 flights on ORD to MKE, most of the route. Its 63.7% on time is about level with the route as a whole at 64.1%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Republic at 78.8% to Envoy at 63.7%. Three of those carriers flew fewer than 365 flights here, so treat their positions as rough.

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on ORD to MKE
Airline	Flights	On time	Avg delay	Cancelled	Grade
Republic Airwaysthin sample	112	78.8%	77 min	7.14%	B−
PSA Airlinesthin sample	26	72.7%	312 min	15.38%	C−
SkyWest Airlines (this page)	4,933	63.7%	93 min	4.64%	D−
Envoy Airthin sample	130	63.7%	67 min	4.62%	D−

Flight by flight

SkyWest flight numbers on ORD to MKE

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 20 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am180 flights76.0%
8am–11am829 flights72.3%
11am–2pm611 flights66.6%
2pm–5pm845 flights61.2%
5pm–8pm1,276 flights55.7%
8pm–5am1,192 flights64.6%

Scale runs 45% to 80%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 55.7% on time, against 76.0% 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 5pm–8pm window is the busiest, with 1,276 flights scheduled in it.

Across the year

SkyWest on ORD to MKE through the year

Darker means more delays. Figures are on-time percentages.September best, December worst

December is the weak month at 52.3% on time, against 73.3% in September. 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. May was the busiest month here, with 512 flights.

Across the week, Tuesday is the strongest day at 70.0% on time and Sunday the weakest at 57.0%. 13 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 158,000 reported delay minutes.

Carrier
39%
Late-arriving aircraft
27%
Extreme weather
17%
National Airspace System
16%

Extreme weather accounts for 17% 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 2.7 times the usual weather exposure. The split is drawn from 158,272 reported delay minutes.

The largest share of delay minutes, 39%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 62,000 of the 158,000 delay minutes reported here.

Cancellations run at 4.64%, against 1.81% nationally. That is about one flight in twenty 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. 17.6% 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 67 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 67.3% on time across 4,932 flights, 4 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 4 points of difference.

The sample behind these figures is 4,933 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.

What to do with this

Booking SkyWest on ORD to MKE

Put together: the delay figures matter less here than the 4.64% cancellation rate. A late arrival costs you an hour and a half; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 4,698 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