Airport month record
SATDEC
San Antonio International in December 2025
- Departures
- 3,588
- Month
- December 2025
- National, same month
- 73.2%
- Carriers
- 8
Historical statistics for December 2025, not live status or a forecast for this year’s December. For today’s conditions at SAT, see live FAA status.
SAT in December lands a B+, 11 points better than the national rate of 73.2%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 3,588 flights, of which United Airlines flew 484 at 84.6% on time.
United Airlines is the most reliable of the four carriers covered here at 84.6% on time across 484 flights.
Key figures
On time
83.7%
Arrivals under 15 minutes late, of 3,554 completed departures
Avg delay
66 min
Across delayed arrivals only, not all flights
Cancelled
0.72%
Nationally in December: 1.55%
Whole year
81.8%
SAT across all twelve months
These figures cover 3,588 departures from San Antonio International in December 2025. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
December next to SAT's other months
Against SAT's own year, December ran 2 points better than the twelve-month rate of 81.8%, which makes it number six of twelve months, best first. Cancellations were unusually low for SAT in December, at 0.72% against 1.28% across the year. Either side of it, November ran 84.1% on time and January 84.8%, so this month sits in line with its neighbours.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 | 3,699 | 76.4% | 77 min | 1.49% | B |
| August 2025 | 3,444 | 81.5% | 79 min | 1.19% | B |
| September 2025 | 3,334 | 85.6% | 71 min | 0.63% | A+ |
| October 2025 | 3,656 | 83.7% | 68 min | 0.38% | B+ |
| November 2025 | 3,440 | 84.1% | 67 min | 1.19% | B |
| December 2025 (this page) | 3,588 | 83.7% | 66 min | 0.72% | B+ |
| January 2026 | 2,921 | 84.8% | 96 min | 3.70% | B− |
| February 2026 | 2,671 | 86.3% | 67 min | 1.27% | A |
| March 2026 | 3,439 | 79.9% | 74 min | 1.37% | B |
| April 2026 | 3,384 | 82.6% | 66 min | 0.74% | B+ |
| May 2026 | 3,485 | 80.7% | 79 min | 1.38% | B |
| June 2026 | 3,393 | 73.5% | 81 min | 1.65% | C |
Departure window
The best time of day to leave SAT in December
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 20 points, against about a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am1,061 flights92.2%
- 8am–11am447 flights90.6%
- 11am–2pm681 flights84.4%
- 2pm–5pm701 flights77.1%
- 5pm–8pm584 flights72.0%
- 8pm–5am114 flights74.6%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 92.2% of the time, against 72.0% for the evening window. That is 20 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 1,061 flights scheduled in it.
Across the week, Tuesday is the strongest day at 86.4% on time and Friday the weakest at 78.6%. 8 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at SAT in December
The four carriers here are closely matched: about a point 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 |
|---|---|---|---|---|---|
| Southwest Airlines | 1,396 | 84.1% | 51 min | 0.14% | B+ |
| American Airlines | 648 | 83.9% | 81 min | 0.31% | B+ |
| Delta Air Lines | 577 | 83.5% | 75 min | 2.60% | B |
| United Airlines | 484 | 84.6% | 72 min | 0.21% | B+ |
| SkyWest Airlinesthin sample | 170 | 88.6% | 82 min | 1.18% | A |
| Spirit Airlinesthin sample | 133 | 79.8% | 89 min | 2.26% | B |
| Frontier Airlinesthin sample | 91 | 84.4% | 68 min | 1.10% | B |
| Alaska Airlinesthin sample | 52 | 63.5% | 54 min | 0.00% | D+ |
No carrier stands out. United tops the table at 84.6%, about a point clear of the bottom, which is inside the range this kind of sample moves year to year.
Route by route
Busiest routes out of SAT in December
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SAT to DFW · Dallas-Fort Worththin sample | 356 | 81.5% | 85 min | 0.00% | B+ |
| SAT to DEN · Denverthin sample | 282 | 84.8% | 64 min | 0.00% | B+ |
| SAT to PHX · Phoenixthin sample | 252 | 87.7% | 63 min | 0.00% | A+ |
| SAT to ATL · Atlantathin sample | 251 | 86.9% | 75 min | 2.39% | A |
| SAT to DAL · Dallasthin sample | 227 | 84.1% | 47 min | 0.00% | B+ |
| SAT to IAH · Houstonthin sample | 216 | 86.0% | 37 min | 0.46% | A+ |
| SAT to LAS · Las Vegasthin sample | 205 | 83.8% | 58 min | 0.49% | B+ |
| SAT to LAX · Los Angelesthin sample | 180 | 83.1% | 62 min | 1.11% | B |
| SAT to ORD · Chicagothin sample | 160 | 76.6% | 87 min | 1.25% | B |
| SAT to HOU · Houstonthin sample | 122 | 87.7% | 41 min | 0.00% | A+ |
| SAT to MCO · Orlandothin sample | 112 | 80.9% | 68 min | 0.89% | B+ |
| SAT to CLT · Charlottethin sample | 108 | 92.5% | 58 min | 0.93% | A+ |
| SAT to SLC · Salt Lake Citythin sample | 88 | 81.2% | 58 min | 3.41% | B− |
| SAT to DTW · Detroitthin sample | 86 | 87.1% | 66 min | 0.00% | A+ |
| SAT to MSP · Minneapolisthin sample | 78 | 82.7% | 66 min | 3.85% | B− |
| SAT to BNA · Nashvillethin sample | 77 | 84.2% | 49 min | 0.00% | B+ |
| SAT to ELP · El Pasothin sample | 77 | 80.5% | 52 min | 0.00% | B+ |
| SAT to BWI · Baltimorethin sample | 71 | 90.0% | 82 min | 1.41% | A |
| SAT to MDW · Chicagothin sample | 60 | 71.7% | 36 min | 0.00% | C+ |
| SAT to SAN · San Diegothin sample | 60 | 74.6% | 50 min | 1.67% | C |
| SAT to IAD · Washingtonthin sample | 58 | 91.4% | 142 min | 0.00% | A+ |
| SAT to EWR · Newarkthin sample | 58 | 82.8% | 57 min | 0.00% | B+ |
| SAT to SEA · Seattlethin sample | 52 | 63.5% | 54 min | 0.00% | D+ |
| SAT to SFO · San Franciscothin sample | 47 | 87.0% | 149 min | 2.13% | A |
| SAT to STL · St. Louisthin sample | 40 | 85.0% | 64 min | 0.00% | A+ |
Delay causes
What held SAT up in December
One category carries most of the weight here. Late-arriving aircraft accounts for 52% of the 38,000 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.
- 52%Late-arriving aircraft
- 26%Carrier
- 21%National Airspace System
- 1%Extreme weather
- 0%Security
52% 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 38,000 reported delay minutes here, that single category outweighs weather by 52 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 38,279 reported delay minutes.
Cancellations are rare at 0.72%, below the national 1.55% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
5.4% of arrivals land an hour or more late, close to the national 10.0%. 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 about an hour, which a normal layover absorbs.
What to do with this
Flying from SAT in December
For a December trip through SAT: expect 83.7% on time and 0.72% cancelled, going by December 2025. The 5am–8am window was the strongest part of the day.
Related
Where to go next
- San Antonio International (SAT), the whole year
- SAT in July76.4%
- SAT in August81.5%
- SAT in September85.6%
- SAT in October83.7%
- SAT in November84.1%
- SAT in January84.8%
- SAT in February86.3%
- SAT in March79.9%
- SAT in April82.6%
- SAT in May80.7%
- SAT in June73.5%
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.