Route reliability record
DEN→AUS
Denver to Austin
- Flights
- 5,231
- Period
- June 2025 to May 2026
- Distance
- 775 mi
- Carriers
- 4
This route lands a B+, about a point worse than the national rate of 77.4%. About one flight in four arrive 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 5,231 flights, of which SkyWest Airlines flew 431 at 82.0% on time.
SkyWest Airlines is the most reliable of the four carriers covered here at 82.0% on time across 431 flights.
Key figures
On time
76.2%
Arrivals under 15 minutes late, of 5,194 completed flights
Avg delay
62 min
Across delayed arrivals only, not all flights
Cancelled
0.57%
National rate is 1.80%
Best carrier
SkyWest
82.0% on time across 431 flights
These figures cover 5,231 flights between June 2025 and May 2026. Beyond the headline rate, 8.1% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Which airline is most reliable on DEN to AUS
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 82.0% of the time; Frontier Airlines manages 72.0%. Sample sizes sit next to every figure, because a two-point gap across 521 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 431 | 82.0% | 90 min | 0.70% | B+ |
| United Airlines | 1,932 | 79.6% | 64 min | 0.62% | B+ |
| Southwest Airlines | 2,347 | 73.4% | 57 min | 0.47% | C+ |
| Frontier Airlines | 521 | 72.0% | 67 min | 0.77% | C+ |
SkyWest leads Frontier by 10 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
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 31 points, against 10 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am543 flights93.1%
- 8am–11am1,365 flights86.5%
- 11am–2pm769 flights76.8%
- 2pm–5pm686 flights69.7%
- 5pm–8pm1,048 flights68.8%
- 8pm–5am820 flights62.3%
Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 62.3% on time, against 93.1% 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.
Across the year
When delays peak on this route
This route's year swings by 29 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 57.5% on time, 29 points below February, the best at 86.0%. 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.
Across the week, Wednesday is the strongest day at 81.1% on time and Friday the weakest at 72.3%. 9 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 47% of the 77,000 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.
- 47%Late-arriving aircraft
- 33%Carrier
- 17%National Airspace System
- 3%Extreme weather
- 0%Security
47% 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 77,000 reported delay minutes here, that single category outweighs weather by 16 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 practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 93.1% on time here.
Cancellations are rare at 0.57%, below the national 1.80% 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.
Connections and stage length
What a delay here actually costs
8.1% of arrivals land an hour or more late, close to the national 8.2%. 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 are the about an hour kind, which a normal layover absorbs.
The 775 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 77.9% on time across 5,231 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 5,231 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.
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 86.0% on time and July 57.5%, a swing of 29 points. If the dates move at all, move them out of July before you think about anything else.
Common questions
DEN to AUS questions
How often is DEN to AUS delayed?
About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 23.8% of the 5,231 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on DEN to AUS?
SkyWest Airlines leads at 82.0% on time across 431 flights. Frontier Airlines is at the other end on 72.0%, a gap of 10 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 DEN to AUS?
The 5am–8am departure window is the strongest at 93.1% on time. The 8pm–5am window is the weakest at 62.3%, 31 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 DEN to AUS?
July is the weakest month at 57.5% on time, compared with 86.0% in February. Across the year that is 29 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
- AUS to DEN — the return legseparate record
- Denver International (DEN) delay statistics
- Austin-Bergstrom International (AUS) delay statistics
- SkyWest Airlines on-time record82.0%
- United Airlines on-time record79.6%
- Southwest Airlines on-time record73.4%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. DEN to AUS and AUS to DEN are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.