Carrier performance at one airport
DL→SAN
Delta Air Lines at San Diego International
- Departures
- 9,609
- Period
- June 2025 to May 2026
- Routes
- 7
- Rank here
- #1 of 10
Delta Air Lines at San Diego earns a A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.4%. When something does go wrong the average delay runs a little over an hour. That rests on 9,609 flights, of which Delta Air Lines flew 9,609 at 86.3% on time.
Measured against the airport rather than the country, Delta Air Lines runs 8 points ahead of the 78.2% 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
86.3%
9,473 completed departures
Avg delay
74 min
Across delayed flights only
Cancelled
1.09%
At SAN, this carrier only
Rank here
#1
Of 10 carriers clearing the floor at SAN
These figures cover 9,609 flights between June 2025 and May 2026. The median arrival is 9 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 86.3% of the time; Hawaiian Airlines manages 58.5%. Sample sizes sit next to every figure, because a two-point gap across 562 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 9,609 | 86.3% | 74 min | 1.09% | A |
| United Airlines | 10,464 | 81.4% | 69 min | 0.75% | B+ |
| JetBlue Airways | 1,642 | 81.1% | 105 min | 2.13% | B |
| Spirit Airlines | 539 | 81.0% | 68 min | 1.30% | B |
| American Airlines | 9,361 | 80.5% | 103 min | 1.83% | B |
| SkyWest Airlines | 14,980 | 79.4% | 58 min | 1.73% | B |
| Alaska Airlines | 12,447 | 78.4% | 58 min | 1.46% | B |
| Southwest Airlines | 37,160 | 74.7% | 51 min | 0.90% | C+ |
| Frontier Airlines | 2,332 | 70.3% | 91 min | 2.14% | C |
| Hawaiian Airlines | 562 | 58.5% | 72 min | 1.42% | D |
The spread between Delta and Hawaiian is 28 points, wide enough that it should decide the booking. On a hundred trips that is 28 more arrivals inside the on-time window.
Route by route
Where Delta Air Lines flies from SAN
Delta Air Lines operates 7 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 ATL · Atlanta | 2,189 | 85.5% | 68 min | 0.78% | A+ |
| SAN to SLC · Salt Lake City | 1,733 | 88.6% | 75 min | 0.63% | A+ |
| SAN to SEA · Seattle | 1,698 | 87.2% | 79 min | 1.00% | A |
| SAN to MSP · Minneapolis | 1,325 | 87.8% | 79 min | 0.60% | A+ |
| SAN to DTW · Detroit | 1,267 | 86.4% | 48 min | 1.03% | A |
| SAN to JFK · New York | 1,033 | 82.5% | 92 min | 3.19% | B− |
| SAN to BOS · Bostonthin sample | 364 | 79.0% | 84 min | 1.65% | B |
Departure window
Best time of day for this operation
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 9,609 flights.
- 5am–8am2,250 flights91.9%
- 8am–11am905 flights87.8%
- 11am–2pm2,585 flights82.6%
- 2pm–5pm1,311 flights84.7%
- 5pm–8pm1,025 flights84.0%
- 8pm–5am1,533 flights86.1%
Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 82.6% on time against 91.9% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise.
Across the year
Seasonal pattern
December is the weak month at 81.5% on time, against 91.1% in April. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days.
Delay causes
What holds this operation up
- 40%Carrier
- 36%Late-arriving aircraft
- 20%National Airspace System
- 4%Extreme weather
- 0%Security
36% 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 96,000 reported delay minutes here, that single category outweighs weather by 10 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 sit at 1.09% against a national 1.80%, which is ordinary. Diversions add another 0.32%.
Badly late arrivals are rare here: only 4.2% 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.
The sample behind these figures is 9,609 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.
Put together: take the 5am–8am departure, avoid December if the dates are flexible, and if two carriers are within a few dollars of each other, Delta is the one with the record behind it. None of that guarantees an on-time arrival; it moves the odds by 28 points, which is the most any booking decision can do.
Common questions
Delta Air Lines at SAN
How often is Delta Air Lines at SAN delayed?
About one flight in seven arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 13.7% of the 9,609 flights in this analysis, against 22.6% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on Delta Air Lines at SAN?
Delta Air Lines leads at 86.3% on time across 9,609 flights. Hawaiian Airlines is at the other end on 58.5%, a gap of 28 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 Delta Air Lines at SAN?
The 5am–8am departure window is the strongest at 91.9% on time. The 11am–2pm window is the weakest at 82.6%, 9 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 December delays on Delta Air Lines at SAN?
December is the weakest month at 81.5% on time, compared with 91.1% in April. Across the year that is 10 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.