Route reliability record
ORD→LAX
Chicago to Los Angeles
- Flights
- 7,121
- Period
- September 2025 to August 2026
- Distance
- 1,744 mi
- Carriers
- 5
This route sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 5 points worse than the national rate of 77.3%. The late ones land a little over an hour behind schedule. That rests on 7,121 ORD to LAX flights, of which United Airlines flew 3,416 at 76.7% on time.
Best time to fly ORD to LAX: a 5am–8am departure, ideally on a Tuesday. Flights in that window arrived on time 85.1% of the time and Tuesday flights 77.3%, against 72.0% for the route overall.
The national on-time rate over the same period is 77.3%, so this route runs 5 points behind the country as a whole. Across a thousand flights that is about 53 extra late arrivals.
Key figures
On time
72.0%
Arrivals under 15 minutes late, of 7,018 completed flights
Avg delay
75 min
Across delayed arrivals only, not all flights
Cancelled
1.33%
National rate is 1.89%
Best carrier
United
76.7% on time across 3,416 flights
These figures cover 7,121 flights between September 2025 and August 2026. Beyond the headline rate, 10.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on ORD to LAX
The choice of carrier is not cosmetic here. United Airlines arrives on time 76.7% of the time; American Airlines manages 67.7%. Sample sizes sit next to every figure, because a two-point gap across 3,092 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 3,416 | 76.7% | 70 min | 0.64% | B+ |
| Delta Air Linesthin sample | 238 | 70.6% | 83 min | 0.00% | C+ |
| Spirit Airlinesthin sample | 130 | 69.7% | 95 min | 6.15% | C− |
| American Airlines | 3,092 | 67.7% | 77 min | 1.78% | C |
| Frontier Airlinesthin sample | 245 | 60.9% | 83 min | 4.08% | D− |
United leads American by 9 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Flights on ORD to LAX
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Chicago to Los Angeles
Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 3 of the top 5 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. ORD → LAXChicago to Los Angeles | United Airlines | 76.2% | 76.7% | 0.64% | 5am–8am, Tue | UA 2361 07:00 |
| 2. ORD → SNAChicago to Santa Ana | United Airlines | 75.7% | 75.9% | 0.29% | 8pm–5am, Tue | — |
| 3. ORD → SNAChicago to Santa Ana | American Airlines | 72.4% | 73.6% | 1.69% | 5am–8am, Tue | AA 1179 18:54 |
| 4. MDW → LAXChicago to Los Angeles | Southwest Airlines | 67.7% | 68.3% | 0.93% | 5am–8am, Tue | — |
| 5. ORD → LAXChicago to Los Angeles | American Airlines | 66.5% | 67.7% | 1.78% | 5am–8am, Tue | AA 1979 10:30 |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
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 25 points, against 9 points between the best and worst carrier.
- 5am–8am1,273 flights85.1%
- 8am–11am1,192 flights78.1%
- 11am–2pm944 flights76.3%
- 2pm–5pm1,400 flights70.4%
- 5pm–8pm1,106 flights59.8%
- 8pm–5am1,206 flights61.2%
Scale runs 50% to 90%.
The 5pm–8pm window is where this operation falls apart: 59.8% on time, against 85.1% 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. The 2pm–5pm window is the busiest, with 1,400 flights scheduled in it.
Explore
Filter ORD to LAX by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On ORD to LAX, the best departure window is 5am–8am at 85.1% on time and the worst is 5pm–8pm at 59.8%, a wide gap of 25.3 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am85.1%
- 8–11am78.1%
- 11am–2pm76.3%
- 2–5pm70.4%
- 5–8pm59.8%
- 8pm–5am61.2%
best all US flightsScale 50% to 95%.
Across the year
When delays peak on this route
This route's year swings by 19 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.
August is the worst month at 62.8% on time, 19 points below September, the best at 81.3%. 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. August was the busiest month here, with 762 flights.
Across the week, Tuesday is the strongest day at 77.3% on time and Sunday the weakest at 67.8%, a spread of 10 points.
Delay causes
Why this route gets delayed
Late-arriving aircraft accounts for 46% of the 148,000 delay minutes carriers reported here, and the remaining four split what is left.
- 46%Late-arriving aircraft
- 30%Carrier
- 17%National Airspace System
- 6%Extreme weather
- 0%Security
46% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 148,000 reported delay minutes here, that single category outweighs weather by 7 to one. The split is drawn from 147,855 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 85.1% on time here.
Cancellations sit at 1.33% against a national 1.89%, which is ordinary. Diversions add another 0.11%.
Connections and stage length
What a delay here actually costs
10.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
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 76.4% on time across 7,119 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.
The sample behind these figures is 7,121 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.
Work out the risk of missing a connection in LAX after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 81.3% on time and August 62.8%, a swing of 19 points. If the dates move at all, move them out of August before you think about anything else. 7,018 completed flights over 12 months sit behind that.
Common questions
ORD to LAX questions
How often is ORD to LAX delayed?
Roughly one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 28.0% of the 7,121 flights in this analysis, against 22.7% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on ORD to LAX?
United Airlines leads at 76.7% on time across 3,416 flights. American Airlines is at the other end on 67.7%, a gap of 9 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on ORD to LAX?
The 5am–8am departure window is the strongest at 85.1% on time. The 5pm–8pm window is the weakest at 59.8%, 25 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 August delays on ORD to LAX?
August is the weakest month at 62.8% on time, compared with 81.3% in September. Across the year that is 19 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
- LAX to ORD — the return legseparate record
- Chicago O'Hare International (ORD) delay statistics
- Los Angeles International (LAX) delay statistics
- United Airlines on ORD to LAX76.7%
- Delta Air Lines on ORD to LAX70.6%
- Spirit Airlines on ORD to LAX69.7%
- American Airlines on ORD to LAX67.7%
- Frontier Airlines on ORD to LAX60.9%
- ORD to LGA, a related route66.6%
- SFO to LAX, a related route70.9%
- ORD to BOS, a related route66.6%
- United Airlines on-time record76.7%
- Delta Air Lines on-time record70.6%
- Spirit Airlines on-time record69.7%
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
Direction matters. ORD to LAX and LAX to ORD are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed ORD to LAX’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.