Airport month record

AUSDEC

Austin-Bergstrom International in December 2025

Departures: 7,528
Month: December 2025
National, same month: 73.2%
Carriers: 10

Historical statistics for December 2025, not live status or a forecast for this year’s December. For today’s conditions at AUS, see live FAA status.

AUS in December lands a B+, 5 points better than the national rate of 73.2%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 7,528 flights, of which Delta Air Lines flew 1,076 at 81.9% on time.

Delta Air Lines is the most reliable of the five carriers covered here at 81.9% on time across 1,076 flights.

On time

77.9%

Arrivals under 15 minutes late, of 7,474 completed departures

Avg delay

70 min

Across delayed arrivals only, not all flights

Cancelled

0.62%

Nationally in December: 1.55%

Whole year

76.6%

AUS across all twelve months

These figures cover 7,528 departures from Austin-Bergstrom 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 AUS's other months

Against AUS's own year, December ran about a point better than the twelve-month rate of 76.6%, which makes it number five of twelve months, best first. Cancellations were unusually low for AUS in December, at 0.62% against 1.21% across the year. Either side of it, November ran 76.0% on time and January 82.8%, so this month sits in line with its neighbours.

AUS month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	7,896	69.6%	80 min	1.61%	C
August 2025	7,214	78.1%	74 min	0.94%	B+
September 2025	6,889	84.2%	65 min	0.39%	B+
October 2025	7,845	76.8%	61 min	0.40%	B+
November 2025	7,346	76.0%	75 min	1.05%	B
December 2025 (this page)	7,528	77.9%	70 min	0.62%	B+
January 2026	6,707	82.8%	84 min	4.65%	B−
February 2026	6,471	81.9%	68 min	0.99%	B+
March 2026	7,973	73.3%	73 min	1.71%	C
April 2026	7,647	77.5%	64 min	0.59%	B+
May 2026	7,831	75.1%	71 min	0.91%	B+
June 2026	7,879	69.1%	69 min	0.98%	C+

Departure window

The best time of day to leave AUS in December

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 19 points, against 5 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am1,526 flights87.1%
8am–11am1,104 flights86.5%
11am–2pm1,307 flights79.6%
2pm–5pm1,710 flights72.7%
5pm–8pm1,338 flights69.5%
8pm–5am543 flights68.1%

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 87.1% of the time, against 68.1% for the overnight window. That is 19 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 1,710 flights scheduled in it.

Across the week, Tuesday is the strongest day at 83.5% on time and Sunday the weakest at 70.7%. 13 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at AUS in December

The five carriers here are closely matched: 5 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.

Carriers at AUS in December 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	3,297	78.1%	49 min	0.12%	B+
Delta Air Lines	1,076	81.9%	79 min	1.58%	B
American Airlines	1,049	78.8%	110 min	0.57%	B+
United Airlines	871	80.4%	66 min	0.46%	B+
SkyWest Airlines	605	77.3%	110 min	0.66%	B+
Alaska Airlinesthin sample	199	72.6%	61 min	1.01%	C
Frontier Airlinesthin sample	144	71.1%	72 min	1.39%	C
Spirit Airlinesthin sample	107	57.8%	81 min	4.67%	D−
JetBlue Airwaysthin sample	86	51.8%	69 min	1.16%	F
Allegiant Airthin sample	63	65.6%	74 min	3.17%	C−

No carrier stands out. Delta tops the table at 81.9%, 5 points clear of the bottom, which is inside the range this kind of sample moves year to year.

Route by route

Busiest routes out of AUS in December

Routes from AUS in December 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
AUS to DEN · Denver	449	75.5%	67 min	0.00%	B+
AUS to DFW · Dallas-Fort Worth	410	78.2%	117 min	0.49%	B+
AUS to ATL · Atlanta	367	83.0%	90 min	2.18%	B
AUS to LAX · Los Angelesthin sample	346	83.2%	58 min	0.00%	B+
AUS to PHX · Phoenixthin sample	290	85.5%	95 min	0.00%	A+
AUS to SFO · San Franciscothin sample	261	83.4%	75 min	0.77%	B+
AUS to LAS · Las Vegasthin sample	255	80.0%	46 min	0.00%	B+
AUS to BNA · Nashvillethin sample	250	78.7%	62 min	0.00%	B+
AUS to MCO · Orlandothin sample	239	73.5%	60 min	0.42%	C+
AUS to ORD · Chicagothin sample	238	72.6%	105 min	0.42%	C+
AUS to IAH · Houstonthin sample	232	82.3%	43 min	0.43%	B+
AUS to EWR · Newarkthin sample	217	64.0%	76 min	2.76%	D
AUS to SAN · San Diegothin sample	198	76.3%	60 min	2.02%	B
AUS to MIA · Miamithin sample	187	81.3%	71 min	0.00%	B+
AUS to DAL · Dallasthin sample	184	80.4%	42 min	0.00%	B+
AUS to JFK · New Yorkthin sample	176	81.1%	68 min	3.41%	B−
AUS to SEA · Seattlethin sample	169	70.2%	53 min	0.59%	C+
AUS to MSY · New Orleansthin sample	162	74.5%	62 min	0.00%	C+
AUS to CLT · Charlottethin sample	151	78.1%	146 min	0.00%	B+
AUS to MSP · Minneapolisthin sample	147	69.4%	73 min	0.00%	C+
AUS to SLC · Salt Lake Citythin sample	140	85.0%	108 min	0.00%	A+
AUS to TPA · Tampathin sample	137	74.5%	58 min	0.00%	C+
AUS to BOS · Bostonthin sample	125	66.4%	64 min	2.40%	C
AUS to FLL · Fort Lauderdalethin sample	121	65.8%	68 min	3.31%	C−
AUS to DTW · Detroitthin sample	107	88.6%	60 min	1.87%	A

Delay causes

What held AUS up in December

One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 115,000 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.

Late-arriving aircraft
48%
Carrier
34%
National Airspace System
17%
Extreme weather
1%
Security
0%

48% 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 115,000 reported delay minutes here, that single category outweighs weather by 47 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 115,410 reported delay minutes.

Cancellations are rare at 0.62%, 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.

7.6% 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 a little over an hour, which a normal layover absorbs.

What to do with this

Flying from AUS in December

For a December trip through AUS: expect 77.9% on time and 0.62% cancelled, going by December 2025. The 5am–8am window was the strongest part of the day.

Austin-Bergstrom International (AUS), the whole year
AUS in July69.6%
AUS in August78.1%
AUS in September84.2%
AUS in October76.8%
AUS in November76.0%
AUS in January82.8%
AUS in February81.9%
AUS in March73.3%
AUS in April77.5%
AUS in May75.1%
AUS in June69.1%

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.

Key figures