Carrier route record
UAMCI→ORD
United Airlines · Kansas City to Chicago
- Flights
- 1,434
- Period
- July 2025 to June 2026
- Share of route
- 35%
- Carriers
- 6
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on MCI to ORD lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 1,434 flights. The strongest carrier on the route with a full sample, Republic Airways, flew 570 at 81.8% on time.
Republic Airways is the most reliable of the three carriers covered here at 81.8% on time across 570 flights.
Key figures
On time
76.5%
Arrivals under 15 minutes late, of 1,403 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
2.02%
National rate is 1.81%
Whole route
74.7%
Every carrier on MCI to ORD, 4,148 flights
These figures cover 1,434 flights between July 2025 and June 2026. Beyond the headline rate, 9.3% 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
United against every carrier on MCI to ORD
United flew 1,434 of the 4,148 flights on MCI to ORD, about 35% of it. Its 76.5% on time is 2 points better than the route as a whole, which runs 74.7%. Ranked by on-time rate it is number two of six carriers on the route, where the range runs from Republic at 81.8% to PSA at 51.4%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Republic Airways arrives on time 81.8% of the time; SkyWest Airlines manages 69.5%. Sample sizes sit next to every figure, because a two-point gap across 943 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 570 | 81.8% | 118 min | 1.58% | B |
| United Airlines (this page) | 1,434 | 76.5% | 82 min | 2.02% | B |
| Envoy Air | 819 | 73.8% | 74 min | 3.66% | C− |
| American Airlinesthin sample | 342 | 73.5% | 135 min | 2.92% | C |
| SkyWest Airlines | 943 | 69.5% | 112 min | 3.71% | C− |
| PSA Airlinesthin sample | 40 | 51.4% | 122 min | 7.50% | F− |
SkyWest Airlines cancels 3.7% 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.
Flight by flight
United flight numbers on MCI to ORD
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 points, against 12 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am173 flights85.7%
- 8am–11am332 flights81.5%
- 11am–2pm356 flights81.0%
- 2pm–5pm331 flights72.9%
- 5pm–8pm242 flights60.9%
- 8pm–5am—
Scale runs 50% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 60.9% on time, against 85.7% 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 356 flights scheduled in it.
Across the year
United on MCI to ORD through the year
July is the worst month at 65.5% on time, 26 points below February, the best at 91.5%. 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. June was the busiest month here, with 167 flights.
Across the week, Thursday is the strongest day at 81.4% on time and Sunday the weakest at 66.5%. 15 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. National Airspace System accounts for 49% of the 27,000 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.
- 49%National Airspace System
- 35%Late-arriving aircraft
- 13%Carrier
- 3%Extreme weather
35% 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 27,000 reported delay minutes here, that single category outweighs weather by 11 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 27,066 reported delay minutes.
49% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 13,000 minutes out of 27,000, against a national NAS share of 21%.
Cancellations sit at 2.02% against a national 1.81%, which is ordinary. Diversions add another 0.14%.
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. 9.3% 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 403 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 71.6% on time across 1,435 flights, 5 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 5 points of difference.
The sample behind these figures is 1,434 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 United on MCI to ORD
Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 91.5% on time and July 65.5%, a swing of 26 points. If the dates move at all, move them out of July before you think about anything else. 1,403 completed flights over 12 months sit behind that.
Related
Where to go next
- MCI to ORD, every carrier
- United on ORD to MCI, the return leg
- Republic Airways on MCI to ORD81.8%
- Envoy Air on MCI to ORD73.8%
- American Airlines on MCI to ORD73.5%
- SkyWest Airlines on MCI to ORD69.5%
- United Airlines network-wide record
- Kansas City International (MCI) delay statistics
- Chicago O'Hare International (ORD) 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.