Carrier route record
UALAX→ORD
United Airlines · Los Angeles to Chicago
- Flights
- 3,380
- Period
- July 2025 to June 2026
- Share of route
- 49%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on LAX to ORD lands a B+, 3 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 3,380 flights, with a median arrival 8 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate United on LAX to ORD from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
80.5%
Arrivals under 15 minutes late, of 3,333 completed flights
Avg delay
67 min
Across delayed arrivals only, not all flights
Cancelled
0.74%
National rate is 1.81%
Whole route
76.4%
Every carrier on LAX to ORD, 6,964 flights
These figures cover 3,380 flights between July 2025 and June 2026. The median arrival is 8 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
United against every carrier on LAX to ORD
United flew 3,380 of the 6,964 flights on LAX to ORD, about 49% of it. Its 80.5% on time is 4 points better than the route as a whole, which runs 76.4%. Ranked by on-time rate it is first of five carriers on the route, where the range runs from United at 80.5% to Frontier at 61.4%. 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines (this page) | 3,380 | 80.5% | 67 min | 0.74% | B+ |
| Spirit Airlinesthin sample | 240 | 77.7% | 75 min | 4.17% | B− |
| American Airlines | 3,051 | 72.9% | 96 min | 2.33% | C |
| Delta Air Linesthin sample | 66 | 68.3% | 86 min | 0.00% | C+ |
| Frontier Airlinesthin sample | 227 | 61.4% | 149 min | 4.85% | D− |
Flight by flight
United flight numbers on LAX 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 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–8am530 flights93.3%
- 8am–11am627 flights82.0%
- 11am–2pm534 flights66.2%
- 2pm–5pm478 flights71.0%
- 5pm–8pm404 flights84.5%
- 8pm–5am807 flights84.1%
Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 66.2% on time against 93.3% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8pm–5am window is the busiest, with 807 flights scheduled in it.
Across the year
United on LAX to ORD through the year
September is the best month on the calendar at 86.3% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. July was the busiest month here, with 320 flights.
Across the week, Tuesday is the strongest day at 85.7% on time and Saturday the weakest at 74.7%. 11 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 42% of the 43,000 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.
- 42%National Airspace System
- 35%Late-arriving aircraft
- 22%Carrier
- 1%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 43,000 reported delay minutes here, that single category outweighs weather by 35 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 43,471 reported delay minutes.
42% 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 18,000 minutes out of 43,000, against a national NAS share of 21%.
Cancellations are rare at 0.74%, 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
6.2% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
At 1,744 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg is a different operation and performs like one: it runs 76.5% on time across 3,380 flights, 4 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 4 points of difference.
The sample behind these figures is 3,380 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 LAX to ORD
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 86.3% on time and November 70.3%, a swing of 16 points. If the dates move at all, move them out of November before you think about anything else. 3,333 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to ORD, every carrier
- United on ORD to LAX, the return leg
- Spirit Airlines on LAX to ORD77.7%
- American Airlines on LAX to ORD72.9%
- Frontier Airlines on LAX to ORD61.4%
- United Airlines network-wide record
- Los Angeles International (LAX) delay statistics
- Chicago O'Hare International (ORD) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.