Carrier route record
UASAT→ORD
United Airlines · San Antonio to Chicago
- Flights
- 889
- Period
- September 2025 to August 2026
- Share of route
- 44%
- Carriers
- 5
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on SAT to ORD lands a B, 2 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 889 flights. The strongest carrier on the route with a full sample, Envoy Air, flew 410 at 76.1% on time.
The US average over the same twelve months is 77.3%, so there is little to separate United on SAT 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
78.9%
Arrivals under 15 minutes late, of 871 completed flights
Avg delay
87 min
Across delayed arrivals only, not all flights
Cancelled
1.12%
National rate is 1.89%
Whole route
76.4%
Every carrier on SAT to ORD, 2,004 flights
These figures cover 889 flights between September 2025 and August 2026. Beyond the headline rate, 8.6% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
United against every carrier on SAT to ORD
United flew 889 of the 2,004 flights on SAT to ORD, about 44% of it. Its 78.9% on time is 3 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 78.9% to SkyWest at 68.4%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: 2 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines (this page) | 889 | 78.9% | 87 min | 1.12% | B |
| Envoy Air | 410 | 76.1% | 69 min | 3.17% | B− |
| Republic Airwaysthin sample | 101 | 74.7% | 54 min | 4.95% | C− |
| American Airlines | 500 | 74.2% | 87 min | 1.80% | C |
| SkyWest Airlinesthin sample | 104 | 68.4% | 52 min | 5.77% | C− |
Envoy Air cancels 3.2% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Flight by flight
United flight numbers on SAT to ORD
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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 2 points between the best and worst carrier.
- 5am–8am351 flights88.0%
- 8am–11am13 flights—
- 11am–2pm151 flights79.9%
- 2pm–5pm206 flights77.5%
- 5pm–8pm168 flights61.2%
- 8pm–5am—
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 61.2% on time, against 88.0% 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 5am–8am window is the busiest, with 351 flights scheduled in it.
Across the year
United on SAT to ORD through the year
Delays peak in March, when the on-time rate falls to 65.1%. February is the strongest month at 89.3%. Moving a flexible trip across that boundary buys 24 points. August was the busiest month here, with 91 flights.
Across the week, Saturday is the strongest day at 84.5% on time and Friday the weakest at 72.3%, a spread of 12 points.
Arrival by arrival
How late United on SAT to ORD runs when it is late
The 184 late arrivals split 70 under half an hour, 39 between 30 and 60 minutes, and 75 an hour or more.
- 15+ min early209 flights24.0%
- Within 15 min478 flights54.9%
- 15–29 min late70 flights8.0%
- 30–59 min late39 flights4.5%
- 1–2 hours late36 flights4.1%
- 2+ hours late39 flights4.5%
Scale runs 0% to 100%.
Share of 871 completed flights by arrival against schedule.
21 of 132 late departures made up the time and arrived on time, 16% of them. In the other direction, 73 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at ORD.
The worst days
Worst days for United on SAT to ORD
The latest arrival of the period was on 21 June 2026, 10 hours 16 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). On three of the five worst days the largest share was filed as a late-arriving aircraft.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 21 June 2026 | 10 hours 16 minutes | Carrier |
| 17 October 2025 | 7 hours 3 minutes | Late-arriving aircraft |
| 10 June 2026 | 7 hours 2 minutes | National Airspace System |
| 5 December 2025 | 6 hours 48 minutes | Late-arriving aircraft |
| 31 August 2026 | 6 hours 11 minutes | Late-arriving aircraft |
Delay causes
Why United runs late on this route
National Airspace System accounts for 43% of the 16,000 delay minutes carriers reported here, and the remaining four split what is left.
- 43%National Airspace System
- 36%Late-arriving aircraft
- 19%Carrier
- 1%Extreme weather
36% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 16,000 reported delay minutes here, that single category outweighs weather by 36 to one. The split is drawn from 16,066 reported delay minutes.
43% 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 6,965 minutes out of 16,000, against a national NAS share of 21%.
Cancellations sit at 1.12% against a national 1.89%, which is ordinary. Diversions add another 0.90%.
Connections and stage length
What a delay here costs
8.6% of arrivals land an hour or more late, close to the national 8.3%, so 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.
The 1,041 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.
The return leg is a different operation and performs like one: it runs 74.0% on time across 889 flights, 5 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 5 points of difference.
One caution: this is a thin sample. 889 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 SAT to ORD
Put together: treat all of this as provisional. 889 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 78.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 871 completed flights over 12 months sit behind that.
Related
Where to go next
- SAT to ORD, every carrier
- United on ORD to SAT, the return leg
- Envoy Air on SAT to ORD76.1%
- Republic Airways on SAT to ORD74.7%
- American Airlines on SAT to ORD74.2%
- SkyWest Airlines on SAT to ORD68.4%
- United Airlines network-wide record
- San Antonio International (SAT) 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 7.05 million flight records
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.