Carrier performance at one airport
WN→SJC
Southwest Airlines at Norman Y. Mineta San Jose International
- Departures
- 26,558
- Period
- July 2025 to June 2026
- Routes
- 25
- Rank here
- #7 of 7
Southwest Airlines at San Jose lands a B+, 2 points 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 roughly 50 minutes on average. That is a workable record, not a spotless one. That rests on 26,558 flights, of which Delta Air Lines flew 2,820 at 92.2% on time.
Measured against the airport rather than the country, Southwest Airlines runs 3 points behind the 83.0% weighted average across all carriers at SJC. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
80.0%
26,361 completed departures
Avg delay
48 min
Across delayed flights only
Cancelled
0.55%
At SJC, this carrier only
Rank here
#7
Of 7 carriers clearing the floor at SJC
These figures cover 27,000 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.
Against the competition
Every carrier at SJC, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 92.2% of the time; Southwest Airlines manages 80.0%. Sample sizes sit next to every figure, because a two-point gap across 26,558 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 2,820 | 92.2% | 76 min | 1.31% | A |
| Hawaiian Airlines | 366 | 92.1% | 102 min | 0.00% | A+ |
| SkyWest Airlines | 6,866 | 88.4% | 64 min | 0.44% | A+ |
| United Airlines | 1,516 | 86.5% | 63 min | 0.53% | A+ |
| Alaska Airlines | 2,763 | 85.3% | 51 min | 1.19% | A |
| American Airlines | 1,783 | 83.2% | 100 min | 1.79% | B |
| Southwest Airlines (this page) | 26,558 | 80.0% | 48 min | 0.55% | B+ |
The spread between Delta and Southwest is 12 points, wide enough that it should decide the booking. On a hundred trips that is 12 more arrivals inside the on-time window.
Route by route
Where Southwest Airlines flies from SJC
Southwest Airlines operates 25 routes out of SJC with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SJC to SAN · San Diego | 3,740 | 70.7% | 45 min | 0.99% | C+ |
| SJC to LAS · Las Vegas | 3,241 | 79.6% | 55 min | 0.46% | B+ |
| SJC to SNA · Santa Ana | 2,662 | 87.0% | 47 min | 0.83% | A+ |
| SJC to BUR · Burbank | 2,188 | 84.6% | 51 min | 1.28% | B |
| SJC to PHX · Phoenix | 1,879 | 78.6% | 48 min | 0.64% | B+ |
| SJC to LAX · Los Angeles | 1,823 | 78.9% | 47 min | 0.44% | B+ |
| SJC to DEN · Denver | 1,527 | 76.3% | 52 min | 0.46% | B+ |
| SJC to ONT · Ontario | 1,316 | 83.5% | 46 min | 0.08% | B+ |
| SJC to LGB · Long Beach | 1,229 | 85.5% | 48 min | 0.16% | A+ |
| SJC to AUS · Austin | 1,143 | 76.2% | 46 min | 0.26% | B+ |
| SJC to PDX · Portland | 973 | 79.1% | 50 min | 0.00% | B+ |
| SJC to SEA · Seattle | 928 | 75.6% | 45 min | 0.00% | B+ |
| SJC to MDW · Chicago | 538 | 83.4% | 36 min | 0.37% | B+ |
| SJC to DAL · Dallas | 458 | 84.7% | 56 min | 0.87% | B+ |
| SJC to HNL · Honolulu | 446 | 82.2% | 49 min | 0.22% | B+ |
| SJC to HOU · Houston | 365 | 90.6% | 29 min | 0.27% | A+ |
| SJC to BOI · Boisethin sample | 330 | 83.0% | 48 min | 0.00% | B+ |
| SJC to EUG · Eugenethin sample | 259 | 73.7% | 44 min | 0.00% | C+ |
| SJC to GEG · Spokanethin sample | 248 | 74.6% | 39 min | 0.00% | C+ |
| SJC to BNA · Nashvillethin sample | 246 | 86.1% | 42 min | 0.00% | A+ |
| SJC to RNO · Renothin sample | 242 | 95.0% | 30 min | 0.00% | A+ |
| SJC to BWI · Baltimorethin sample | 242 | 83.0% | 32 min | 0.41% | B+ |
| SJC to SLC · Salt Lake Citythin sample | 224 | 83.4% | 53 min | 0.45% | B+ |
| SJC to PSP · Palm Springsthin sample | 198 | 80.0% | 55 min | 1.01% | B |
| SJC to OGG · Kahuluithin sample | 105 | 90.5% | 35 min | 0.00% | A+ |
Departure window
Best time of day for this operation
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 27 points, against 12 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am4,479 flights95.7%
- 8am–11am5,808 flights90.1%
- 11am–2pm4,632 flights79.5%
- 2pm–5pm4,669 flights69.9%
- 5pm–8pm4,314 flights68.3%
- 8pm–5am2,656 flights68.7%
Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 95.7% of the time, against 68.3% for the evening window. That is 27 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 5,808 flights scheduled in it.
Across the year
Seasonal pattern
June is the worst month at 67.8% on time, 22 points below January, 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. July was the busiest month here, with 2,505 flights.
Delay causes
What holds this operation up
- 56%Late-arriving aircraft
- 24%Carrier
- 19%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 253,000 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 252,717 reported delay minutes.
Cancellations are rare at 0.55%, 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.
Badly late arrivals are rare here: only 4.8% land an hour or more behind schedule, against 8.1% 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.
26,558 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 89.9% on time and June 67.8%, a swing of 22 points. If the dates move at all, move them out of June before you think about anything else. 26,361 completed flights over 12 months sit behind that.
Common questions
Southwest Airlines at SJC
How often is Southwest Airlines at 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 20.0% of the 26,558 flights in this analysis, against 22.4% nationally. Delayed flights are late by roughly 50 minutes on average.
Which airline is most reliable on Southwest Airlines at SJC?
Delta Air Lines leads at 92.2% on time across 2,820 flights. Southwest Airlines is at the other end on 80.0%, a gap of 12 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 Southwest Airlines at SJC?
The 5am–8am departure window is the strongest at 95.7% on time. The 5pm–8pm window is the weakest at 68.3%, 27 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 Southwest Airlines at SJC?
June is the weakest month at 67.8% on time, compared with 89.9% in January. 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
- Southwest Airlines network-wide record
- Norman Y. Mineta San Jose International (SJC) all carriers
- SJC to SAN route record70.7%
- SJC to LAS route record79.6%
- SJC to SNA route record87.0%
- SJC to BUR route record84.6%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.