Route reliability record
MKE→ORD
Milwaukee to Chicago
- Flights
- 5,166
- Period
- June 2025 to May 2026
- Distance
- 67 mi
- Carriers
- 4
This route carries a cancellation problem, not just a delay problem: 4.2% 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 C− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 5,166 flights, with a median arrival 1 minutes late.
The national on-time rate over the same period is 77.4%, so this route runs 11 points behind the country as a whole. Across a thousand flights that is about 108 extra late arrivals.
Key figures
On time
66.6%
Arrivals under 15 minutes late, of 4,948 completed flights
Avg delay
94 min
Across delayed arrivals only, not all flights
Cancelled
4.18%
National rate is 1.80%
Best carrier
SkyWest
66.4% on time across 4,895 flights
These figures cover 5,166 flights between June 2025 and May 2026. Beyond the headline rate, 15.6% 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
Which airline is most reliable on MKE to ORD
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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airwaysthin sample | 114 | 72.4% | 85 min | 7.89% | C− |
| Envoy Airthin sample | 130 | 69.7% | 74 min | 6.15% | C− |
| SkyWest Airlines | 4,895 | 66.4% | 94 min | 3.96% | C− |
| PSA Airlinesthin sample | 26 | 54.5% | 176 min | 15.38% | F− |
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 33 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–8am1,593 flights79.1%
- 8am–11am1,202 flights67.0%
- 11am–2pm811 flights64.3%
- 2pm–5pm836 flights60.6%
- 5pm–8pm676 flights45.7%
- 8pm–5am48 flights56.5%
Scale runs 35% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 45.7% on time, against 79.1% 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.
Across the year
When delays peak on this route
This route's year swings by 18 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 57.4% on time, 18 points below February, the best at 75.1%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck.
Across the week, Tuesday is the strongest day at 70.9% on time and Sunday the weakest at 60.7%. 10 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Carrier accounts for 46% of the 155,000 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.
- 46%Carrier
- 23%Late-arriving aircraft
- 20%National Airspace System
- 11%Extreme weather
- 0%Security
The largest share of delay minutes, 46%, 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 72,000 of the 155,000 delay minutes reported here.
Cancellations run at 4.18%, against 1.80% nationally. That is about one flight in 25 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 actually costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 15.6% of arrivals land a full hour or more behind schedule, against 8.2% 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 runs 63.7% on time across 5,167 flights, within 3 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 5,166 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 this route
Put together: the delay figures matter less here than the 4.18% 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.
Common questions
MKE to ORD questions
How often is MKE to ORD delayed?
About one flight in three arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 33.4% of the 5,166 flights in this analysis, against 22.6% nationally. Delayed flights are late by an hour and a half on average.
How reliable is MKE to ORD compared with the rest of the country?
66.6% of flights arrive on time here against a national 77.4%, a difference of 11 points against it. That is worth a C− on this site's grading scale.
What time of day has the fewest delays on MKE to ORD?
The 5am–8am departure window is the strongest at 79.1% on time. The 5pm–8pm window is the weakest at 45.7%, 33 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on MKE to ORD?
July is the weakest month at 57.4% on time, compared with 75.1% in February. Across the year that is 18 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- ORD to MKE — the return legseparate record
- Chicago O'Hare International (ORD) delay statistics
- Republic Airways on-time record72.4%
- Envoy Air on-time record69.7%
- SkyWest Airlines on-time record66.4%
- What a cancellation rate actually tells you (and what it hides)
- The best time of day to fly, according to 7.05 million flight records
Direction matters. MKE to ORD and ORD to MKE are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.