Route reliability record
ATL→SAT
Atlanta to San Antonio
- Flights
- 2,962
- Period
- September 2025 to August 2026
- Distance
- 874 mi
- Carriers
- 3
This route lands a B, 4 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 about an hour on average. That rests on 2,962 ATL to SAT flights, with a median arrival 7 minutes early.
Best time to fly ATL to SAT: a 8am–11am departure, ideally on a Wednesday. Flights in that window arrived on time 87.0% of the time and Wednesday flights 89.4%, against 81.1% for the route overall.
The US average over the same twelve months is 77.3%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
81.1%
Arrivals under 15 minutes late, of 2,909 completed flights
Avg delay
56 min
Across delayed arrivals only, not all flights
Cancelled
1.65%
National rate is 1.89%
Best carrier
Delta
81.1% on time across 2,596 flights
These figures cover 2,962 flights between September 2025 and August 2026. The median arrival is 7 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
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 ATL to SAT
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Southwest Airlinesthin sample | 292 | 82.1% | 46 min | 0.34% | B+ |
| Delta Air Lines | 2,596 | 81.1% | 55 min | 1.85% | B |
| Frontier Airlinesthin sample | 74 | 75.7% | 106 min | 0.00% | B+ |
Flight by flight
Flights on ATL 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.
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 13 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am652 flights87.0%
- 11am–2pm596 flights83.0%
- 2pm–5pm772 flights80.8%
- 5pm–8pm398 flights73.8%
- 8pm–5am544 flights77.8%
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 87.0% of the time, against 73.8% for the evening window. That is 13 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 772 flights scheduled in it.
Explore
Filter ATL 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 ATL to SAT, the best departure window is 8am–11am at 87.0% on time and the worst is 5pm–8pm at 73.8%, a wide gap of 13.2 points. All US flights leaving 8am–11am ran 83.9%.
- 5–8am—
- 8–11am87.0%
- 11am–2pm83.0%
- 2–5pm80.8%
- 5–8pm73.8%
- 8pm–5am77.8%
best all US flightsScale 60% to 95%. Cells under 30 flights show a dash.
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.
July is the worst month at 68.2% on time, 19 points below February, the best at 86.7%. 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. October was the busiest month here, with 275 flights.
Across the week, Wednesday is the strongest day at 89.4% on time and Sunday the weakest at 75.4%, a spread of 14 points.
Delay causes
Why this route gets delayed
Carrier accounts for 47% of the 31,000 delay minutes carriers reported here, and the remaining four split what is left.
- 47%Carrier
- 32%Late-arriving aircraft
- 17%National Airspace System
- 4%Extreme weather
- 0%Security
The largest share of delay minutes, 47%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 14,000 of the 31,000 delay minutes reported here. The split is drawn from 30,928 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 87.0% on time here.
Cancellations sit at 1.65% against a national 1.89%, which is ordinary. Diversions add another 0.14%.
Connections and stage length
What a delay here actually costs
5.3% 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 about an hour, which a normal layover absorbs.
The 874 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 85.9% on time across 2,962 flights, 5 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 5 points of difference.
The sample behind these figures is 2,962 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. February runs 86.7% on time and July 68.2%, a swing of 19 points. If the dates move at all, move them out of July before you think about anything else. 2,909 completed flights over 12 months sit behind that.
Common questions
ATL to SAT questions
How often is ATL to SAT delayed?
About one flight in five arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 18.9% of the 2,962 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
How reliable is ATL to SAT compared with the rest of the country?
81.1% of flights arrive on time here against a national 77.3%, a difference of 4 points in its favour. That is worth a B on this site's grading scale.
What time of day has the fewest delays on ATL to SAT?
The 8am–11am departure window is the strongest at 87.0% on time. The 5pm–8pm window is the weakest at 73.8%, 13 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 July delays on ATL to SAT?
July is the weakest month at 68.2% on time, compared with 86.7% in February. 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
- SAT to ATL — the return legseparate record
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- San Antonio International (SAT) delay statistics
- Southwest Airlines on ATL to SAT82.1%
- Delta Air Lines on ATL to SAT81.1%
- ATL to LGA, a related route72.3%
- DFW to SAT, a related route67.8%
- ATL to MCO, a related route70.3%
- Southwest Airlines on-time record82.1%
- Delta Air Lines on-time record81.1%
- Frontier Airlines on-time record75.7%
- The best time of day to fly, according to 7.05 million flight records
- Worst months to fly in the US, ranked by the data
Direction matters. ATL to SAT and SAT to ATL are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed ATL 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.