Route reliability record
LAS→SAN
Las Vegas to San Diego
- Flights
- 6,131
- Period
- June 2025 to May 2026
- Distance
- 258 mi
- Carriers
- 5
This route draws a C. About one flight in three arrive at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 6,131 flights, of which SkyWest Airlines flew 1,654 at 74.6% on time.
SkyWest Airlines is the most reliable of the three carriers covered here at 74.6% on time across 1,654 flights.
Key figures
On time
67.7%
Arrivals under 15 minutes late, of 6,055 completed flights
Avg delay
56 min
Across delayed arrivals only, not all flights
Cancelled
1.09%
National rate is 1.80%
Best carrier
SkyWest
74.6% on time across 1,654 flights
These figures cover 6,131 flights between June 2025 and May 2026. Beyond the headline rate, 8.7% 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 LAS to SAN
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 74.6% of the time; Southwest Airlines manages 63.8%. Sample sizes sit next to every figure, because a two-point gap across 3,726 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Alaska Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Spirit Airlinesthin sample | 347 | 78.1% | 66 min | 1.15% | B |
| SkyWest Airlines | 1,654 | 74.6% | 63 min | 1.27% | C |
| Frontier Airlines | 403 | 66.2% | 97 min | 1.74% | C |
| Southwest Airlines | 3,726 | 63.8% | 49 min | 0.94% | D+ |
SkyWest leads Southwest by 11 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 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am900 flights88.7%
- 8am–11am1,272 flights71.6%
- 11am–2pm914 flights63.7%
- 2pm–5pm1,215 flights65.5%
- 5pm–8pm1,046 flights58.5%
- 8pm–5am784 flights57.4%
Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 57.4% on time, against 88.7% 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.
Across the year
When delays peak on this route
This route's year swings by 14 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.
Delays peak in May, when the on-time rate falls to 58.4%. August is the strongest month at 72.7%. Moving a flexible trip across that boundary buys 14 points.
Across the week, Wednesday is the strongest day at 78.6% on time and Friday the weakest at 59.4%. 19 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 109,000 reported delay minutes.
- 35%Late-arriving aircraft
- 32%Carrier
- 30%National Airspace System
- 2%Extreme weather
- 0%Security
35% 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 109,000 reported delay minutes here, that single category outweighs weather by 14 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 88.7% on time here.
Cancellations sit at 1.09% against a national 1.80%, which is ordinary. Diversions add another 0.15%.
Connections and stage length
What a delay here actually costs
8.7% 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.
At 258 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 75.5% on time across 6,129 flights, 8 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 8 points of difference.
The sample behind these figures is 6,131 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. August runs 72.7% on time and May 58.4%, a swing of 14 points. If the dates move at all, move them out of May before you think about anything else.
Common questions
LAS to SAN questions
How often is LAS to SAN delayed?
About one flight in three arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 32.3% of the 6,131 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on LAS to SAN?
SkyWest Airlines leads at 74.6% on time across 1,654 flights. Southwest Airlines is at the other end on 63.8%, a gap of 11 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 SAN?
The 5am–8am departure window is the strongest at 88.7% on time. The 8pm–5am window is the weakest at 57.4%, 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 May delays on LAS to SAN?
May is the weakest month at 58.4% on time, compared with 72.7% in August. Across the year that is 14 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
- SAN to LAS — the return legseparate record
- Harry Reid International (LAS) delay statistics
- San Diego International (SAN) delay statistics
- Alaska Airlines on-time record100.0%
- Spirit Airlines on-time record78.1%
- SkyWest Airlines on-time record74.6%
- 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. LAS to SAN and SAN 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, June 2025 to May 2026. Updated monthly. How this data is collected.