Route reliability record
LAS→AUS
Las Vegas to Austin
- Flights
- 2,865
- Period
- July 2025 to June 2026
- Distance
- 1,090 mi
- Carriers
- 5
This route sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.6%. The late ones land about 55 minutes behind schedule. That rests on 2,865 flights, of which Southwest Airlines flew 2,176 at 73.3% on time.
The national on-time rate over the same period is 77.6%, so this route runs 4 points behind the country as a whole. Across a thousand flights that is about 41 extra late arrivals.
Key figures
On time
73.5%
Arrivals under 15 minutes late, of 2,845 completed flights
Avg delay
55 min
Across delayed arrivals only, not all flights
Cancelled
0.42%
National rate is 1.81%
Best carrier
Southwest
73.3% on time across 2,176 flights
These figures cover 2,865 flights between July 2025 and June 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.
Carrier by carrier
Which airline is most reliable on LAS to AUS
The two carriers here are closely matched: 6 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Allegiant Airthin sample | 20 | 85.0% | 83 min | 0.00% | A+ |
| Frontier Airlinesthin sample | 291 | 81.8% | 64 min | 1.37% | B |
| Southwest Airlines | 2,176 | 73.3% | 50 min | 0.23% | C+ |
| Delta Air Lines | 365 | 67.8% | 73 min | 0.82% | C+ |
| Spirit Airlinesthin sample | 13 | 61.5% | 47 min | 0.00% | D+ |
No carrier stands out. Southwest tops the table at 73.3%, 6 points clear of the bottom, which is inside the range this kind of sample moves year to year.
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 35 points, against 6 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am582 flights90.7%
- 8am–11am535 flights81.4%
- 11am–2pm457 flights72.9%
- 2pm–5pm467 flights62.8%
- 5pm–8pm731 flights63.4%
- 8pm–5am93 flights55.9%
Scale runs 45% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 55.9% on time, against 90.7% 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. The 5pm–8pm window is the busiest, with 731 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 22 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 62.1% on time, 22 points below December, 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 259 flights.
Across the week, Wednesday is the strongest day at 84.8% on time and Sunday the weakest at 67.1%. 18 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 41,000 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
- 34%Carrier
- 16%National Airspace System
- 2%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 41,000 reported delay minutes here, that single category outweighs weather by 23 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 41,359 reported delay minutes.
The largest share of delay minutes, 34%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 14,000 of the 41,000 delay minutes reported here.
Cancellations are rare at 0.42%, below the national 1.81% 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
7.8% of arrivals land an hour or more late, close to the national 8.1%. 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 55 minutes kind, which a normal layover absorbs.
The 1,090 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 73.8% on time across 2,866 flights, within half a point 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 2,865 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. December runs 83.8% on time and July 62.1%, a swing of 22 points. If the dates move at all, move them out of July before you think about anything else. 2,845 completed flights over 12 months sit behind that.
Common questions
LAS to AUS questions
How often is LAS 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 26.5% of the 2,865 flights in this analysis, against 22.4% nationally. Delayed flights are late by about 55 minutes on average.
Which airline is most reliable on LAS to AUS?
Southwest Airlines leads at 73.3% on time across 2,176 flights. Delta Air Lines is at the other end on 67.8%, a gap of 6 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 LAS to AUS?
The 5am–8am departure window is the strongest at 90.7% on time. The 8pm–5am window is the weakest at 55.9%, 35 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 LAS to AUS?
July is the weakest month at 62.1% on time, compared with 83.8% in December. Across the year that is 22 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 LAS — the return legseparate record
- Harry Reid International (LAS) delay statistics
- Austin-Bergstrom International (AUS) delay statistics
- Allegiant Air on-time record85.0%
- Frontier Airlines on-time record81.8%
- Southwest Airlines on-time record73.3%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. LAS to AUS and AUS to LAS 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, July 2025 to June 2026. Updated monthly. How this data is collected.