Carrier route record
UAORD→JAX
United Airlines · Chicago to Jacksonville
- Flights
- 893
- Period
- July 2025 to June 2026
- Share of route
- 43%
- Carriers
- 6
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on ORD to JAX sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 893 flights, with a median arrival 5 minutes early.
The national on-time rate over the same period is 77.6%, so United on ORD to JAX runs 4 points behind the country as a whole. Across a thousand flights that is about 40 extra late arrivals.
Key figures
On time
73.6%
Arrivals under 15 minutes late, of 888 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
0.45%
National rate is 1.81%
Whole route
72.7%
Every carrier on ORD to JAX, 2,062 flights
These figures cover 893 flights between July 2025 and June 2026. Beyond the headline rate, 10.8% 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 JAX
United flew 893 of the 2,062 flights on ORD to JAX, about 43% of it. Its 73.6% on time is about level with the route as a whole at 72.7%. Ranked by on-time rate it is number five of six carriers on the route, where the range runs from PSA at 100.0% to American at 62.3%. Four 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PSA Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Republic Airwaysthin sample | 317 | 80.3% | 58 min | 2.21% | B |
| SkyWest Airlinesthin sample | 150 | 77.9% | 61 min | 1.33% | B |
| Envoy Airthin sample | 237 | 75.8% | 56 min | 0.42% | B+ |
| United Airlines (this page) | 893 | 73.6% | 82 min | 0.45% | C+ |
| American Airlines | 464 | 62.3% | 102 min | 2.59% | D |
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 27 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–8am177 flights90.3%
- 8am–11am129 flights77.3%
- 11am–2pm216 flights74.9%
- 2pm–5pm32 flights71.9%
- 5pm–8pm322 flights63.8%
- 8pm–5am17 flights—
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 63.8% on time, against 90.3% 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 322 flights scheduled in it.
Across the year
United on ORD to JAX through the year
July is the worst month at 46.7% on time, 37 points below February, the best at 83.6%. 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. March was the busiest month here, with 103 flights.
Across the week, Thursday is the strongest day at 78.6% on time and Saturday the weakest at 64.9%. 14 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. Late-arriving aircraft accounts for 58% of the 19,000 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.
- 58%Late-arriving aircraft
- 22%Carrier
- 16%National Airspace System
- 5%Extreme weather
58% 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 19,000 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 19,106 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 90.3% on time here.
Cancellations are rare at 0.45%, 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. 10.8% 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 864 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 77.8% on time across 893 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.
One caution: this is a thin sample. 893 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 JAX
Put together: treat all of this as provisional. 893 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 73.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 888 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to JAX, every carrier
- United on JAX to ORD, the return leg
- Republic Airways on ORD to JAX80.3%
- SkyWest Airlines on ORD to JAX77.9%
- Envoy Air on ORD to JAX75.8%
- American Airlines on ORD to JAX62.3%
- United Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
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.