Route reliability record
LAX→SJC
Los Angeles to San Jose
- Flights
- 4,400
- Period
- June 2025 to May 2026
- Distance
- 308 mi
- Carriers
- 6
This route earns a A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.4%. When something does go wrong the average delay runs about 50 minutes. That rests on 4,400 flights, of which SkyWest Airlines flew 2,149 at 91.1% on time.
Set against the rest of the country, this route's record is 10 points better than the US average of 77.4%. That gap is worth roughly 99 fewer late arrivals for every thousand flights.
Key figures
On time
87.3%
Arrivals under 15 minutes late, of 4,369 completed flights
Avg delay
50 min
Across delayed arrivals only, not all flights
Cancelled
0.68%
National rate is 1.80%
Best carrier
SkyWest
91.1% on time across 2,149 flights
These figures cover 4,400 flights between June 2025 and May 2026. The median arrival is 12 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Which airline is most reliable on LAX to SJC
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 91.1% of the time; Southwest Airlines manages 83.3%. Sample sizes sit next to every figure, because a two-point gap across 1,806 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| SkyWest Airlines | 2,149 | 91.1% | 53 min | 0.33% | A+ |
| Delta Air Linesthin sample | 361 | 86.5% | 50 min | 3.32% | A− |
| Southwest Airlines | 1,806 | 83.3% | 48 min | 0.55% | B+ |
| Frontier Airlinesthin sample | 77 | 78.9% | 56 min | 1.30% | B |
| American Airlinesthin sample | 6 | 66.7% | 39 min | 0.00% | C+ |
SkyWest leads Southwest by 8 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 16 points, against 8 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am614 flights94.7%
- 8am–11am659 flights92.8%
- 11am–2pm908 flights91.4%
- 2pm–5pm711 flights86.8%
- 5pm–8pm873 flights80.4%
- 8pm–5am635 flights78.8%
Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 94.7% of the time, against 78.8% for the overnight window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on.
Across the year
When delays peak on this route
Twelve months, one bar each, drawn from the same 4,400 flights. The strip shows how much of this route's record is set by the calendar rather than by the operation.
Delays peak in May, when the on-time rate falls to 80.7%. August is the strongest month at 92.1%. Moving a flexible trip across that boundary buys 11 points.
Across the week, Tuesday is the strongest day at 90.9% on time and Sunday the weakest at 81.9%. 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 46% of the 28,000 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.
- 46%Late-arriving aircraft
- 43%Carrier
- 6%National Airspace System
- 5%Extreme weather
- 0%Security
46% 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 28,000 reported delay minutes here, that single category outweighs weather by 9 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 largest share of delay minutes, 43%, 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 12,000 of the 28,000 delay minutes reported here.
Cancellations are rare at 0.68%, 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
Badly late arrivals are rare here: only 3.5% land an hour or more behind schedule, against 8.2% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
At 308 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 runs 87.3% on time across 4,405 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 4,400 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: avoid the 8pm–5am departure. It runs 78.8% on time against 94.7% for the 5am–8am slot, and that 16 points is the largest single thing you control here. SkyWest Airlines is the strongest operator if the fares are close.
Common questions
LAX to SJC questions
How often is LAX to SJC delayed?
About one flight in eight arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 12.7% of the 4,400 flights in this analysis, against 22.6% nationally. Delayed flights are late by about 50 minutes on average.
Which airline is most reliable on LAX to SJC?
SkyWest Airlines leads at 91.1% on time across 2,149 flights. Southwest Airlines is at the other end on 83.3%, a gap of 8 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 LAX to SJC?
The 5am–8am departure window is the strongest at 94.7% on time. The 8pm–5am window is the weakest at 78.8%, 16 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 LAX to SJC?
May is the weakest month at 80.7% on time, compared with 92.1% in August. Across the year that is 11 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
- SJC to LAX — the return legseparate record
- Los Angeles International (LAX) delay statistics
- Norman Y. Mineta San Jose International (SJC) delay statistics
- United Airlines on-time record100.0%
- SkyWest Airlines on-time record91.1%
- Delta Air Lines on-time record86.5%
- 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. LAX to SJC and SJC to LAX 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.