Carrier performance at one airport
WN→SJC
Southwest Airlines at Norman Y. Mineta San Jose International
- Departures
- 26,718
- Period
- June 2025 to May 2026
- Routes
- 25
- Rank here
- #7 of 7
Southwest Airlines at San Jose lands a B+, 4 points better than the national rate of 77.4%. 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 26,718 flights, of which Delta Air Lines flew 2,727 at 91.8% on time.
Measured against the airport rather than the country, Southwest Airlines runs 3 points behind the 83.5% 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
80.9%
26,520 completed departures
Avg delay
48 min
Across delayed flights only
Cancelled
0.56%
At SJC, this carrier only
Rank here
#7
Of 7 carriers clearing the floor at SJC
These figures cover 27,000 flights between June 2025 and May 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 91.8% of the time; Southwest Airlines manages 80.9%. Sample sizes sit next to every figure, because a two-point gap across 26,718 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 2,727 | 91.8% | 90 min | 1.32% | A |
| Hawaiian Airlines | 426 | 91.1% | 111 min | 0.00% | A+ |
| SkyWest Airlines | 6,970 | 88.4% | 65 min | 0.44% | A+ |
| United Airlines | 1,524 | 86.2% | 69 min | 0.52% | A+ |
| Alaska Airlines | 2,637 | 85.4% | 53 min | 1.40% | A |
| American Airlines | 1,774 | 83.3% | 95 min | 1.75% | B |
| Southwest Airlines (this page) | 26,718 | 80.9% | 48 min | 0.56% | B+ |
Delta leads Southwest by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
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 | 3,746 | 72.5% | 45 min | 1.04% | C |
| SJC to LAS · Las Vegas | 3,261 | 79.7% | 54 min | 0.55% | B+ |
| SJC to SNA · Santa Ana | 2,654 | 87.6% | 48 min | 0.94% | A+ |
| SJC to BUR · Burbank | 2,220 | 84.0% | 51 min | 1.22% | B |
| SJC to PHX · Phoenix | 1,885 | 79.8% | 47 min | 0.53% | B+ |
| SJC to LAX · Los Angeles | 1,808 | 80.5% | 47 min | 0.33% | B+ |
| SJC to DEN · Denver | 1,524 | 77.4% | 54 min | 0.46% | B+ |
| SJC to ONT · Ontario | 1,317 | 84.1% | 48 min | 0.00% | B+ |
| SJC to LGB · Long Beach | 1,222 | 85.7% | 50 min | 0.16% | A+ |
| SJC to AUS · Austin | 1,163 | 77.4% | 47 min | 0.26% | B+ |
| SJC to PDX · Portland | 999 | 79.7% | 51 min | 0.00% | B+ |
| SJC to SEA · Seattle | 948 | 76.0% | 47 min | 0.00% | B+ |
| SJC to MDW · Chicago | 550 | 83.4% | 39 min | 0.36% | B+ |
| SJC to DAL · Dallas | 487 | 86.0% | 60 min | 1.03% | A |
| SJC to HNL · Honolulu | 445 | 85.8% | 49 min | 0.22% | A+ |
| SJC to HOU · Houston | 365 | 91.2% | 28 min | 0.27% | A+ |
| SJC to BOI · Boisethin sample | 332 | 86.4% | 48 min | 0.00% | A+ |
| SJC to GEG · Spokanethin sample | 257 | 77.8% | 43 min | 0.00% | B+ |
| SJC to EUG · Eugenethin sample | 253 | 77.1% | 38 min | 0.00% | B+ |
| SJC to BNA · Nashvillethin sample | 249 | 85.5% | 44 min | 0.00% | A+ |
| SJC to RNO · Renothin sample | 243 | 95.5% | 30 min | 0.00% | A+ |
| SJC to BWI · Baltimorethin sample | 238 | 85.2% | 32 min | 0.42% | A+ |
| SJC to SLC · Salt Lake Citythin sample | 235 | 86.3% | 55 min | 0.43% | A+ |
| SJC to PSP · Palm Springsthin sample | 199 | 80.1% | 55 min | 1.01% | B |
| SJC to OGG · Kahuluithin sample | 106 | 91.5% | 37 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 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am4,476 flights95.6%
- 8am–11am5,907 flights90.8%
- 11am–2pm4,716 flights80.3%
- 2pm–5pm4,689 flights71.5%
- 5pm–8pm4,304 flights69.1%
- 8pm–5am2,626 flights70.8%
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 95.6% of the time, against 69.1% 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.
Across the year
Seasonal pattern
Delays peak in October, when the on-time rate falls to 76.2%. January is the strongest month at 89.9%. Moving a flexible trip across that boundary buys 14 points.
Delay causes
What holds this operation up
- 55%Late-arriving aircraft
- 24%Carrier
- 20%National Airspace System
- 1%Extreme weather
- 0%Security
55% 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 245,000 reported delay minutes here, that single category outweighs weather by 55 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.
Cancellations are rare at 0.56%, 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.
Badly late arrivals are rare here: only 4.6% 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.
26,718 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 October 76.2%, a swing of 14 points. If the dates move at all, move them out of October before you think about anything else.
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 19.1% of the 26,718 flights in this analysis, against 22.6% 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 91.8% on time across 2,727 flights. Southwest Airlines is at the other end on 80.9%, 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 Southwest Airlines at SJC?
The 5am–8am departure window is the strongest at 95.6% on time. The 5pm–8pm window is the weakest at 69.1%, 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 October delays on Southwest Airlines at SJC?
October is the weakest month at 76.2% on time, compared with 89.9% in January. 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
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.