Route reliability record
ATL→SAN
Atlanta to San Diego
- Flights
- 2,413
- Period
- July 2025 to June 2026
- Distance
- 1,892 mi
- Carriers
- 2
This route lands a B+, about a point 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 45 minutes on average. That is a workable record, not a spotless one. That rests on 2,413 flights, with a median arrival 3 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.8%
Arrivals under 15 minutes late, of 2,381 completed flights
Avg delay
47 min
Across delayed arrivals only, not all flights
Cancelled
0.62%
National rate is 1.81%
Best carrier
Delta
78.4% on time across 2,172 flights
These figures cover 2,413 flights between July 2025 and June 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.
Carrier by carrier
Which airline is most reliable on ATL to SAN
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 |
|---|---|---|---|---|---|
| Alaska Airlinesthin sample | 241 | 82.0% | 38 min | 0.00% | B+ |
| Delta Air Lines | 2,172 | 78.4% | 48 min | 0.69% | B+ |
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 14 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am437 flights87.3%
- 11am–2pm404 flights79.9%
- 2pm–5pm626 flights78.9%
- 5pm–8pm581 flights74.6%
- 8pm–5am365 flights73.8%
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 87.3% of the time, against 73.8% for the overnight window. That is 14 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 626 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 14 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 71.4% on time, 14 points below March, the best at 85.8%. 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. October was the busiest month here, with 233 flights.
Across the week, Wednesday is the strongest day at 85.2% on time and Thursday the weakest at 74.2%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Carrier accounts for 45% of the 24,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 45%Carrier
- 28%National Airspace System
- 22%Late-arriving aircraft
- 5%Extreme weather
The largest share of delay minutes, 45%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 11,000 of the 24,000 delay minutes reported here. The split is drawn from 23,688 reported delay minutes.
Cancellations are rare at 0.62%, 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.
Connections and stage length
What a delay here actually costs
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.
At 1,892 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg is a different operation and performs like one: it runs 85.5% on time across 2,412 flights, 7 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 7 points of difference.
The sample behind these figures is 2,413 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 this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. March runs 85.8% on time and July 71.4%, a swing of 14 points. If the dates move at all, move them out of July before you think about anything else. 2,381 completed flights over 12 months sit behind that.
Common questions
ATL to SAN questions
How often is ATL to SAN 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 21.2% of the 2,413 flights in this analysis, against 22.4% nationally. Delayed flights are late by roughly 45 minutes on average.
How reliable is ATL to SAN compared with the rest of the country?
78.8% of flights arrive on time here against a national 77.6%, a difference of about a point in its favour. That is worth a B+ on this site's grading scale.
What time of day has the fewest delays on ATL to SAN?
The 8am–11am departure window is the strongest at 87.3% on time. The 8pm–5am window is the weakest at 73.8%, 14 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 July delays on ATL to SAN?
July is the weakest month at 71.4% on time, compared with 85.8% in March. 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
- SAN to ATL — the return legseparate record
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- San Diego International (SAN) delay statistics
- Alaska Airlines on-time record82.0%
- Delta Air Lines on-time record78.4%
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
Direction matters. ATL to SAN and SAN to ATL are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.