Route reliability record
PHX→SJC
Phoenix to San Jose
- Flights
- 3,016
- Period
- July 2025 to June 2026
- Distance
- 621 mi
- Carriers
- 4
This route lands a B+, about a point better than the national rate of 77.6%. About one flight in five 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 3,016 flights, of which Southwest Airlines flew 1,866 at 77.7% on time.
The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
79.0%
Arrivals under 15 minutes late, of 2,998 completed flights
Avg delay
58 min
Across delayed arrivals only, not all flights
Cancelled
0.50%
National rate is 1.81%
Best carrier
Southwest
77.7% on time across 1,866 flights
These figures cover 3,016 flights between July 2025 and June 2026. The median arrival is 5 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 PHX to SJC
The two carriers here are closely matched: about a point 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 |
|---|---|---|---|---|---|
| Envoy Airthin sample | 220 | 87.2% | 43 min | 0.45% | A+ |
| SkyWest Airlinesthin sample | 293 | 86.2% | 74 min | 0.68% | A+ |
| Southwest Airlines | 1,866 | 77.7% | 48 min | 0.38% | B+ |
| American Airlines | 637 | 76.5% | 84 min | 0.78% | B+ |
No carrier stands out. Southwest tops the table at 77.7%, about a point 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 31 points, against about a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am376 flights96.0%
- 8am–11am640 flights89.1%
- 11am–2pm444 flights83.1%
- 2pm–5pm534 flights76.1%
- 5pm–8pm443 flights64.9%
- 8pm–5am579 flights66.9%
Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 64.9% on time, against 96.0% 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 8am–11am window is the busiest, with 640 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.
June is the worst month at 67.7% on time, 22 points below September, the best at 89.9%. 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 299 flights.
Across the week, Tuesday is the strongest day at 83.5% on time and Sunday the weakest at 75.3%. 8 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 56% of the 37,000 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.
- 56%Late-arriving aircraft
- 39%Carrier
- 4%National Airspace System
- 1%Extreme weather
- 0%Security
56% 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 37,000 reported delay minutes here, that single category outweighs weather by 56 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 36,564 reported delay minutes.
The largest share of delay minutes, 39%, 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 37,000 delay minutes reported here.
Cancellations are rare at 0.50%, 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
6.3% 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 an hour kind, which a normal layover absorbs.
The 621 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 is a different operation and performs like one: it runs 82.0% on time across 3,031 flights, 3 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 3 points of difference.
The sample behind these figures is 3,016 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. September runs 89.9% on time and June 67.7%, a swing of 22 points. If the dates move at all, move them out of June before you think about anything else. 2,998 completed flights over 12 months sit behind that.
Common questions
PHX to SJC questions
How often is PHX to SJC delayed?
About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 21.0% of the 3,016 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on PHX to SJC?
Southwest Airlines leads at 77.7% on time across 1,866 flights. American Airlines is at the other end on 76.5%, a gap of about a point. 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 PHX to SJC?
The 5am–8am departure window is the strongest at 96.0% on time. The 5pm–8pm window is the weakest at 64.9%, 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 June delays on PHX to SJC?
June is the weakest month at 67.7% on time, compared with 89.9% in September. 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
- SJC to PHX — the return legseparate record
- Phoenix Sky Harbor International (PHX) delay statistics
- Norman Y. Mineta San Jose International (SJC) delay statistics
- Envoy Air on-time record87.2%
- SkyWest Airlines on-time record86.2%
- Southwest Airlines on-time record77.7%
- 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. PHX to SJC and SJC to PHX 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.