Carrier route record
AASAN→ORD
American Airlines · San Diego to Chicago
- Flights
- 1,386
- Period
- July 2025 to June 2026
- Share of route
- 36%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with American Airlines.
American on SAN to ORD 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 an hour and a half on average. That is a workable record, not a spotless one. That rests on 1,386 flights. The strongest carrier on the route with a full sample, United Airlines, flew 1,672 at 82.0% on time.
The US average over the same twelve months is 77.6%, so there is little to separate American on SAN 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
77.3%
Arrivals under 15 minutes late, of 1,346 completed flights
Avg delay
93 min
Across delayed arrivals only, not all flights
Cancelled
1.80%
National rate is 1.81%
Whole route
78.0%
Every carrier on SAN to ORD, 3,807 flights
These figures cover 1,386 flights between July 2025 and June 2026. Beyond the headline rate, 8.9% 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 SAN to ORD
American flew 1,386 of the 3,807 flights on SAN to ORD, about 36% of it. Its 77.3% on time is about level with the route as a whole at 78.0%. Ranked by on-time rate it is number two of four carriers on the route, where the range runs from United at 82.0% to Frontier at 38.3%. One 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 82.0% of the time; Alaska Airlines manages 73.5%. Sample sizes sit next to every figure, because a two-point gap across 688 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 1,672 | 82.0% | 76 min | 0.54% | B+ |
| American Airlines (this page) | 1,386 | 77.3% | 93 min | 1.80% | B |
| Alaska Airlines | 688 | 73.5% | 64 min | 2.33% | C |
| Frontier Airlinesthin sample | 61 | 38.3% | 111 min | 1.64% | F |
United leads Alaska by 9 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
American flight numbers on SAN 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 31 points, against 9 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am406 flights87.8%
- 8am–11am127 flights82.1%
- 11am–2pm358 flights67.2%
- 2pm–5pm295 flights62.2%
- 5pm–8pm—
- 8pm–5am200 flights92.9%
Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is the strongest at 92.9% on time. The full set of windows spans 31 points.
Across the year
American on SAN to ORD through the year
August is the worst month at 66.4% on time, 21 points below May, the best at 87.2%. 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. July was the busiest month here, with 152 flights.
Across the week, Tuesday is the strongest day at 84.1% on time and Sunday the weakest at 74.2%. 10 points is a smaller lever than departure hour, but it is free.
Delay causes
Why American runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 28,000 reported delay minutes.
- 40%Late-arriving aircraft
- 33%Carrier
- 15%National Airspace System
- 12%Extreme weather
Extreme weather accounts for 12% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.0 times the usual weather exposure. The split is drawn from 28,432 reported delay minutes.
40% 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 28,000 reported delay minutes here, that single category outweighs weather by 3 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.
Cancellations sit at 1.80% against a national 1.81%, which is ordinary. Diversions add another 1.08%.
Connections and stage length
What a delay here costs
8.9% 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 an hour and a half, which a normal layover absorbs.
At 1,723 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 66.3% on time across 1,385 flights, 11 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 11 points of difference.
The sample behind these figures is 1,386 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 SAN to ORD
Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 87.2% on time and August 66.4%, a swing of 21 points. If the dates move at all, move them out of August before you think about anything else. 1,346 completed flights over 12 months sit behind that.
Related
Where to go next
- SAN to ORD, every carrier
- American on ORD to SAN, the return leg
- United Airlines on SAN to ORD82.0%
- Alaska Airlines on SAN to ORD73.5%
- American Airlines network-wide record
- San Diego International (SAN) 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.