Carrier route record
WNSJC→PHX
Southwest Airlines · San Jose to Phoenix
- Flights
- 1,869
- Period
- September 2025 to August 2026
- Share of route
- 62%
- Carriers
- 4
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on SJC to PHX lands a B+, level with the national rate of 77.3%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That rests on 1,869 flights, with a median arrival 3 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate Southwest on SJC to PHX from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
77.7%
Arrivals under 15 minutes late, of 1,854 completed flights
Avg delay
49 min
Across delayed arrivals only, not all flights
Cancelled
0.64%
National rate is 1.89%
Whole route
80.9%
Every carrier on SJC to PHX, 3,013 flights
These figures cover 1,869 flights between September 2025 and August 2026. The median arrival is 3 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.
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Carrier by carrier
Southwest against every carrier on SJC to PHX
Southwest flew 1,869 of the 3,013 flights on SJC to PHX, most of the route. Its 77.7% on time is 3 points worse than the route as a whole, which runs 80.9%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Envoy at 89.4% to Southwest at 77.7%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Envoy Airthin sample | 190 | 89.4% | 52 min | 1.05% | A |
| American Airlines | 685 | 86.1% | 90 min | 0.88% | A+ |
| SkyWest Airlinesthin sample | 269 | 84.2% | 97 min | 1.12% | B |
| Southwest Airlines (this page) | 1,869 | 77.7% | 49 min | 0.64% | B+ |
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When Southwest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 35 points, against half a point between the best and worst carrier.
- 5am–8am319 flights95.9%
- 8am–11am343 flights91.5%
- 11am–2pm271 flights81.8%
- 2pm–5pm380 flights64.1%
- 5pm–8pm336 flights69.4%
- 8pm–5am220 flights60.6%
Scale runs 50% to 100%.
The 8pm–5am window is where this operation falls apart: 60.6% on time, against 95.9% 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 2pm–5pm window is the busiest, with 380 flights scheduled in it.
Across the year
Southwest on SJC to PHX through the year
June is the worst month at 63.6% on time, 25 points below January, the best at 88.4%. 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. May was the busiest month here, with 180 flights.
Across the week, Saturday is the strongest day at 86.6% on time and Sunday the weakest at 72.4%, a spread of 14 points.
Arrival by arrival
How late Southwest on SJC to PHX runs when it is late
The 413 late arrivals split 167 under half an hour, 145 between 30 and 60 minutes, and 101 an hour or more.
- 15+ min early237 flights12.8%
- Within 15 min1,204 flights64.9%
- 15–29 min late167 flights9.0%
- 30–59 min late145 flights7.8%
- 1–2 hours late77 flights4.2%
- 2+ hours late24 flights1.3%
Scale runs 0% to 100%.
Share of 1,854 completed flights by arrival against schedule.
110 of 502 late departures made up the time and arrived on time, 22% of them. Only 21 left on time and still arrived late.
The worst days
Worst days for Southwest on SJC to PHX
The latest arrival of the period was on 26 September 2025, 6 hours 27 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The five worst days are spread across September, May, July and November, with no single month standing out.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 26 September 2025 | 6 hours 27 minutes | Late-arriving aircraft |
| 26 May 2026 | 5 hours 1 minute | Carrier |
| 12 July 2026 | 4 hours 4 minutes | Late-arriving aircraft |
| 5 November 2025 | 4 hours | National Airspace System |
| 9 November 2025 | 3 hours 34 minutes | National Airspace System |
Delay causes
Why Southwest runs late on this route
Late-arriving aircraft accounts for 62% of the 20,000 delay minutes carriers reported here, and the remaining four split what is left.
- 62%Late-arriving aircraft
- 22%Carrier
- 15%National Airspace System
- 1%Extreme weather
62% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 20,000 reported delay minutes here, that single category outweighs weather by 58 to one. The split is drawn from 20,171 reported delay minutes.
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 95.9% on time here.
Cancellations are rare at 0.64%, below the national 1.89% 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 costs
5.4% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 50 minutes, 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.
The return leg runs 76.9% on time across 1,837 flights, within about 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 1,869 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 Southwest on SJC to PHX
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 88.4% on time and June 63.6%, a swing of 25 points. If the dates move at all, move them out of June before you think about anything else. 1,854 completed flights over 12 months sit behind that.
Related
Where to go next
- SJC to PHX, every carrier
- Southwest on PHX to SJC, the return leg
- Envoy Air on SJC to PHX89.4%
- American Airlines on SJC to PHX86.1%
- SkyWest Airlines on SJC to PHX84.2%
- Southwest Airlines network-wide record
- Norman Y. Mineta San Jose International (SJC) delay statistics
- Phoenix Sky Harbor International (PHX) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.