Carrier performance at one airport
WN→SAN
Southwest Airlines at San Diego International
- Departures
- 37,660
- Period
- July 2025 to June 2026
- Routes
- 25
- Rank here
- #8 of 10
Southwest Airlines at San Diego sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.6%. The late ones land about 50 minutes behind schedule. That rests on 37,660 flights, of which Delta Air Lines flew 9,577 at 86.8% on time.
Measured against the airport rather than the country, Southwest Airlines runs 4 points behind the 78.0% weighted average across all carriers at SAN. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
73.5%
37,233 completed departures
Avg delay
51 min
Across delayed flights only
Cancelled
0.91%
At SAN, this carrier only
Rank here
#8
Of 10 carriers clearing the floor at SAN
These figures cover 38,000 flights between July 2025 and June 2026. The median arrival is 2 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 SAN, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 86.8% of the time; Hawaiian Airlines manages 60.8%. Sample sizes sit next to every figure, because a two-point gap across 487 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 9,577 | 86.8% | 76 min | 1.13% | A |
| Spirit Airlines | 400 | 82.2% | 65 min | 1.50% | B |
| JetBlue Airways | 1,646 | 81.5% | 106 min | 2.25% | B |
| United Airlines | 10,504 | 81.3% | 69 min | 0.75% | B+ |
| American Airlines | 9,358 | 80.6% | 102 min | 1.86% | B |
| SkyWest Airlines | 14,952 | 79.8% | 58 min | 1.77% | B |
| Alaska Airlines | 12,721 | 78.8% | 57 min | 1.46% | B |
| Southwest Airlines (this page) | 37,660 | 73.5% | 51 min | 0.91% | C+ |
| Frontier Airlines | 2,265 | 72.3% | 82 min | 2.03% | C |
| Hawaiian Airlines | 487 | 60.8% | 78 min | 1.64% | D |
The spread between Delta and Hawaiian is 26 points, wide enough that it should decide the booking. On a hundred trips that is 26 more arrivals inside the on-time window.
Route by route
Where Southwest Airlines flies from SAN
Southwest Airlines operates 25 routes out of SAN 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 |
|---|---|---|---|---|---|
| SAN to SMF · Sacramento | 3,807 | 75.5% | 47 min | 0.55% | B+ |
| SAN to SJC · San Jose | 3,741 | 76.0% | 49 min | 0.80% | B+ |
| SAN to LAS · Las Vegas | 3,730 | 74.7% | 53 min | 1.21% | C |
| SAN to PHX · Phoenix | 3,184 | 74.4% | 50 min | 1.54% | C |
| SAN to OAK · Oakland | 2,940 | 74.5% | 50 min | 1.09% | C |
| SAN to DEN · Denver | 2,387 | 72.4% | 57 min | 0.75% | C+ |
| SAN to SFO · San Francisco | 1,935 | 58.4% | 61 min | 1.09% | D |
| SAN to DAL · Dallas | 1,569 | 69.0% | 48 min | 1.85% | C |
| SAN to AUS · Austin | 1,429 | 68.2% | 50 min | 0.56% | C+ |
| SAN to BWI · Baltimore | 1,142 | 79.4% | 47 min | 1.49% | B |
| SAN to MDW · Chicago | 1,080 | 78.1% | 52 min | 0.93% | B+ |
| SAN to BNA · Nashville | 1,065 | 75.0% | 46 min | 0.94% | B+ |
| SAN to HOU · Houston | 961 | 71.4% | 45 min | 0.42% | C+ |
| SAN to RNO · Reno | 924 | 74.2% | 50 min | 0.76% | C+ |
| SAN to HNL · Honolulu | 729 | 81.8% | 47 min | 0.82% | B+ |
| SAN to ABQ · Albuquerque | 687 | 77.6% | 57 min | 1.02% | B |
| SAN to TUS · Tucson | 653 | 75.4% | 62 min | 0.31% | B+ |
| SAN to SAT · San Antonio | 610 | 71.4% | 52 min | 0.49% | C+ |
| SAN to FAT · Fresno | 512 | 80.2% | 44 min | 1.17% | B |
| SAN to STL · St. Louis | 474 | 76.0% | 49 min | 0.21% | B+ |
| SAN to MCO · Orlando | 438 | 77.7% | 44 min | 0.68% | B+ |
| SAN to SLC · Salt Lake City | 408 | 76.6% | 45 min | 0.25% | B+ |
| SAN to MCI · Kansas City | 390 | 73.2% | 55 min | 0.77% | C+ |
| SAN to BOI · Boise | 372 | 68.0% | 52 min | 0.00% | C+ |
| SAN to ELP · El Pasothin sample | 361 | 76.8% | 52 min | 0.55% | B+ |
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 30 points, against 26 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am5,181 flights91.9%
- 8am–11am8,524 flights84.9%
- 11am–2pm6,445 flights70.9%
- 2pm–5pm6,617 flights62.3%
- 5pm–8pm6,784 flights64.2%
- 8pm–5am4,109 flights64.2%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.9% of the time, against 62.3% for the afternoon window. That is 30 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 8,524 flights scheduled in it.
Across the year
Seasonal pattern
June is the worst month at 59.8% on time, 23 points below January, the best at 82.5%. 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. June was the busiest month here, with 3,560 flights.
Delay causes
What holds this operation up
- 61%Late-arriving aircraft
- 23%Carrier
- 14%National Airspace System
- 1%Extreme weather
- 0%Security
61% 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 501,000 reported delay minutes here, that single category outweighs weather by 61 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 501,316 reported delay minutes.
Cancellations sit at 0.91% against a national 1.81%, which is ordinary. Diversions add another 0.23%.
7.0% 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 50 minutes kind, which a normal layover absorbs.
37,660 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 82.5% on time and June 59.8%, a swing of 23 points. If the dates move at all, move them out of June before you think about anything else. 37,233 completed flights over 12 months sit behind that.
Common questions
Southwest Airlines at SAN
How often is Southwest Airlines at SAN delayed?
About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 26.5% of the 37,660 flights in this analysis, against 22.4% nationally. Delayed flights are late by about 50 minutes on average.
Which airline is most reliable on Southwest Airlines at SAN?
Delta Air Lines leads at 86.8% on time across 9,577 flights. Hawaiian Airlines is at the other end on 60.8%, a gap of 26 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 SAN?
The 5am–8am departure window is the strongest at 91.9% on time. The 2pm–5pm window is the weakest at 62.3%, 30 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 SAN?
June is the weakest month at 59.8% on time, compared with 82.5% in January. Across the year that is 23 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
- San Diego International (SAN) all carriers
- SAN to SMF route record75.5%
- SAN to SJC route record76.0%
- SAN to LAS route record74.7%
- SAN to PHX route record74.4%
- 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.