Carrier route record

UAORD→EYW

United Airlines · Chicago to Key West

Flights: 138
Period: July 2025 to June 2026
Share of route: 19%
Carriers: 3

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

United on ORD to EYW lands a B+, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 138 flights, with a median arrival 4 minutes early.

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

On time

77.2%

Arrivals under 15 minutes late, of 136 completed flights

Avg delay

75 min

Across delayed arrivals only, not all flights

Cancelled

0.72%

National rate is 1.81%

Whole route

80.5%

Every carrier on ORD to EYW, 717 flights

These figures cover 138 flights between July 2025 and June 2026. Beyond the headline rate, 9.6% 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

United against every carrier on ORD to EYW

United flew 138 of the 717 flights on ORD to EYW, about 19% of it. Its 77.2% on time is 3 points worse than the route as a whole, which runs 80.5%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from Envoy at 82.0% to United at 77.2%. One 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 EYW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Envoy Air	407	82.0%	63 min	1.23%	B
Republic Airwaysthin sample	172	79.6%	55 min	1.74%	B
United Airlines (this page)thin sample	138	77.2%	75 min	0.72%	B+

Departure window

When United runs best on this route

Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 138 flights.

There are not enough flights in each departure window to split United's ORD to EYW record by time of day without the percentages moving on noise. The headline rate of 77.2% is the reliable figure here.

Across the year

United on ORD to EYW through the year

Oct–Dec 202514 flights—
Jan–Mar 202695 flights81.7%
Apr–Jun 202629 flights—

Scale runs 75% to 85%. 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 77.2% on time across 138 flights.

Split by quarter, United on ORD to EYW logged 14 flights in Oct–Dec 2025, 95 flights in Jan–Mar 2026 and 29 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 77.2% annual figure is the one to use.

Delay causes

Why United runs late on this route

One category carries most of the weight here. National Airspace System accounts for 43% of the 2,316 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.

National Airspace System
43%
Late-arriving aircraft
35%
Carrier
16%
Extreme weather
6%

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 2,316 reported delay minutes here, that single category outweighs weather by 5 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 2,316 reported delay minutes.

43% 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 995 minutes out of 2,316, against a national NAS share of 21%.

Cancellations are rare at 0.72%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

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. 9.6% 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.

The 1,251 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg is a different operation and performs like one: it runs 54.5% on time across 138 flights, 23 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 23 points of difference.

One caution: this is a thin sample. 138 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 United on ORD to EYW

Put together: treat all of this as provisional. 138 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 77.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 136 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