Route reliability record
ORD→SAT
Chicago to San Antonio
- Flights
- 2,001
- Period
- September 2025 to August 2026
- Distance
- 1,041 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 2,001 ORD to SAT flights, of which Envoy Air flew 410 at 76.3% on time.
Best time to fly ORD to SAT: a 8am–11am departure, ideally on a Tuesday. Flights in that window arrived on time 80.2% of the time and Tuesday flights 79.0%, against 72.7% for the route overall.
Envoy Air is the most reliable of the three carriers covered here at 76.3% on time across 410 flights.
Key figures
On time
72.7%
Arrivals under 15 minutes late, of 1,961 completed flights
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
1.75%
National rate is 1.89%
Best carrier
Envoy
76.3% on time across 410 flights
These figures cover 2,001 flights between September 2025 and August 2026. Beyond the headline rate, 11.7% 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 SAT
The choice of carrier is not cosmetic here. Envoy Air arrives on time 76.3% of the time; American Airlines manages 64.3%. Sample sizes sit next to every figure, because a two-point gap across 497 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airwaysthin sample | 101 | 82.3% | 62 min | 3.96% | B− |
| SkyWest Airlinesthin sample | 104 | 79.0% | 61 min | 3.85% | B− |
| Envoy Air | 410 | 76.3% | 62 min | 2.44% | B |
| United Airlines | 889 | 74.0% | 73 min | 0.90% | C+ |
| American Airlines | 497 | 64.3% | 86 min | 1.81% | D |
The spread between Envoy and American is 12 points, wide enough that it should decide the booking. On a hundred trips that is 12 more arrivals inside the on-time window.
Flight by flight
Flights on ORD to SAT
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 San Antonio
Every airline on this route, ranked by how often a scheduled flight actually operated and arrived on time, with its best departure time and most punctual flight number. No nearby airport pair beat these.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. ORD → SATChicago to San Antonio | Envoy Air | 74.4% | 76.3% | 2.44% | 8am–11am, Thu | — |
| 2. ORD → SATChicago to San Antonio | United Airlines | 73.3% | 74.0% | 0.90% | 8am–11am, Tue | UA 490 09:15 |
| 3. ORD → SATChicago to San Antonio | American Airlines | 63.1% | 64.3% | 1.81% | 5pm–8pm, Fri | — |
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 20 points, against 12 points between the best and worst carrier.
- 5am–8am—
- 8am–11am678 flights80.2%
- 11am–2pm366 flights77.1%
- 2pm–5pm261 flights73.6%
- 5pm–8pm147 flights71.0%
- 8pm–5am549 flights60.4%
Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 60.4% on time, against 80.2% for the 8am–11am 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 8am–11am window is the busiest, with 678 flights scheduled in it.
Explore
Filter ORD to SAT 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 SAT, the best departure window is 8am–11am at 80.2% on time and the worst is 8pm–5am at 60.4%, a wide gap of 19.8 points. All US flights leaving 8am–11am ran 83.9%.
- 5–8am—
- 8–11am80.2%
- 11am–2pm77.1%
- 2–5pm73.6%
- 5–8pm71.0%
- 8pm–5am60.4%
best all US flightsScale 50% to 95%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 24 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 59.6% on time, 24 points below October, the best at 83.8%. 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. March was the busiest month here, with 179 flights.
Across the week, Tuesday is the strongest day at 79.0% on time and Sunday the weakest at 69.2%, a spread of 10 points.
Delay causes
Why this route gets delayed
Late-arriving aircraft accounts for 51% of the 40,000 delay minutes carriers reported here, and the remaining four split what is left.
- 51%Late-arriving aircraft
- 25%Carrier
- 16%National Airspace System
- 7%Extreme weather
- 0%Security
51% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 40,000 reported delay minutes here, that single category outweighs weather by 7 to one. The split is drawn from 39,749 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 80.2% on time here.
Cancellations sit at 1.75% against a national 1.89%, which is ordinary. Diversions add another 0.25%.
Connections and stage length
What a delay here actually costs
11.7% 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.
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 76.4% on time across 2,004 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 2,001 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 SAT 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. October runs 83.8% on time and August 59.6%, a swing of 24 points. If the dates move at all, move them out of August before you think about anything else. 1,961 completed flights over 12 months sit behind that.
Common questions
ORD to SAT questions
How often is ORD to SAT 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 27.3% of the 2,001 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 SAT?
Envoy Air leads at 76.3% on time across 410 flights. American Airlines is at the other end on 64.3%, a gap of 12 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 SAT?
The 8am–11am departure window is the strongest at 80.2% on time. The 8pm–5am window is the weakest at 60.4%, 20 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 SAT?
August is the weakest month at 59.6% on time, compared with 83.8% in October. Across the year that is 24 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
- SAT to ORD — the return legseparate record
- Chicago O'Hare International (ORD) delay statistics
- San Antonio International (SAT) delay statistics
- Republic Airways on ORD to SAT82.3%
- SkyWest Airlines on ORD to SAT79.0%
- Envoy Air on ORD to SAT76.3%
- United Airlines on ORD to SAT74.0%
- American Airlines on ORD to SAT64.3%
- ORD to LGA, a related route66.6%
- DFW to SAT, a related route67.8%
- ORD to BOS, a related route66.6%
- Republic Airways on-time record82.3%
- SkyWest Airlines on-time record79.0%
- Envoy Air on-time record76.3%
- Why the first flight of the morning is statistically safest
- Same route, different airline: where the carrier you pick matters most
Direction matters. ORD to SAT and SAT to ORD are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed ORD to SAT’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.