Carrier route record
AALAS→ORD
American Airlines · Las Vegas to Chicago
- Flights
- 1,848
- Period
- July 2025 to June 2026
- Share of route
- 35%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with American Airlines.
American on LAS 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 1,848 flights. The strongest carrier on the route with a full sample, United Airlines, flew 2,330 at 79.3% on time.
The US average over the same twelve months is 77.6%, so there is little to separate American on LAS 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
76.2%
Arrivals under 15 minutes late, of 1,791 completed flights
Avg delay
99 min
Across delayed arrivals only, not all flights
Cancelled
2.27%
National rate is 1.81%
Whole route
76.5%
Every carrier on LAS to ORD, 5,297 flights
These figures cover 1,848 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
American against every carrier on LAS to ORD
American flew 1,848 of the 5,297 flights on LAS to ORD, about 35% of it. Its 76.2% on time is about level with the route as a whole at 76.5%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from Spirit at 83.6% to Southwest at 66.6%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. United Airlines arrives on time 79.3% of the time; Southwest Airlines manages 66.6%. Sample sizes sit next to every figure, because a two-point gap across 669 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 266 | 83.6% | 54 min | 1.50% | B |
| United Airlines | 2,330 | 79.3% | 71 min | 0.43% | B+ |
| American Airlines (this page) | 1,848 | 76.2% | 99 min | 2.27% | B |
| Frontier Airlinesthin sample | 184 | 68.6% | 88 min | 4.35% | C− |
| Southwest Airlines | 669 | 66.6% | 58 min | 0.30% | C+ |
The spread between United and Southwest is 13 points, wide enough that it should decide the booking. On a hundred trips that is 13 more arrivals inside the on-time window.
Flight by flight
American flight numbers on LAS to ORD
Departure window
When American runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am353 flights90.4%
- 8am–11am418 flights84.6%
- 11am–2pm312 flights70.8%
- 2pm–5pm394 flights61.5%
- 5pm–8pm55 flights69.4%
- 8pm–5am316 flights73.8%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 90.4% of the time, against 61.5% for the afternoon window. That is 29 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 418 flights scheduled in it.
Across the year
American on LAS to ORD through the year
Delays peak in March, when the on-time rate falls to 67.8%. February is the strongest month at 84.6%. Moving a flexible trip across that boundary buys 17 points. April was the busiest month here, with 194 flights.
Across the week, Tuesday is the strongest day at 80.2% on time and Monday the weakest at 73.7%. 7 points is a smaller lever than departure hour, but it is free.
Delay causes
Why American runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 53% of the 42,000 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.
- 53%Late-arriving aircraft
- 31%Carrier
- 15%National Airspace System
- 1%Extreme weather
53% 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 42,000 reported delay minutes here, that single category outweighs weather by 53 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 42,059 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 90.4% on time here.
Cancellations sit at 2.27% against a national 1.81%, which is ordinary. Diversions add another 0.81%.
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 1,514 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 66.8% on time across 1,852 flights, 9 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 9 points of difference.
The sample behind these figures is 1,848 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 American on LAS to ORD
Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 84.6% on time and March 67.8%, a swing of 17 points. If the dates move at all, move them out of March before you think about anything else. 1,791 completed flights over 12 months sit behind that.
Related
Where to go next
- LAS to ORD, every carrier
- American on ORD to LAS, the return leg
- Spirit Airlines on LAS to ORD83.6%
- United Airlines on LAS to ORD79.3%
- Frontier Airlines on LAS to ORD68.6%
- Southwest Airlines on LAS to ORD66.6%
- American Airlines network-wide record
- Harry Reid International (LAS) 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.