Route reliability record
PHX→SAN
Phoenix to San Diego
- Flights
- 5,868
- Period
- June 2025 to May 2026
- Distance
- 304 mi
- Carriers
- 5
This route sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.4%. The late ones land about an hour behind schedule. That rests on 5,868 flights, of which Frontier Airlines flew 414 at 75.4% on time.
Frontier Airlines is the most reliable of the four carriers covered here at 75.4% on time across 414 flights.
Key figures
On time
74.1%
Arrivals under 15 minutes late, of 5,777 completed flights
Avg delay
57 min
Across delayed arrivals only, not all flights
Cancelled
1.31%
National rate is 1.80%
Best carrier
Frontier
75.4% on time across 414 flights
These figures cover 5,868 flights between June 2025 and May 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.
Carrier by carrier
Which airline is most reliable on PHX to SAN
The choice of carrier is not cosmetic here. Frontier Airlines arrives on time 75.4% of the time; SkyWest Airlines manages 68.6%. Sample sizes sit next to every figure, because a two-point gap across 375 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Alaska Airlinesthin sample | 218 | 85.4% | 56 min | 2.29% | A |
| Frontier Airlines | 414 | 75.4% | 84 min | 1.45% | B |
| American Airlines | 1,672 | 75.0% | 63 min | 0.66% | B+ |
| Southwest Airlines | 3,189 | 73.4% | 50 min | 1.07% | C |
| SkyWest Airlines | 375 | 68.6% | 56 min | 5.60% | C− |
SkyWest Airlines cancels 5.6% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
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 31 points, against 7 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am857 flights90.8%
- 8am–11am1,142 flights81.5%
- 11am–2pm865 flights76.6%
- 2pm–5pm1,244 flights69.0%
- 5pm–8pm956 flights67.3%
- 8pm–5am804 flights59.4%
Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 59.4% on time, against 90.8% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in.
Across the year
When delays peak on this route
This route's year swings by 13 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.
Delays peak in May, when the on-time rate falls to 67.5%. February is the strongest month at 80.3%. Moving a flexible trip across that boundary buys 13 points.
Across the week, Saturday is the strongest day at 83.6% on time and Friday the weakest at 68.2%. 15 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. Late-arriving aircraft accounts for 47% of the 85,000 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.
- 47%Late-arriving aircraft
- 29%Carrier
- 22%National Airspace System
- 3%Extreme weather
- 1%Security
47% 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 85,000 reported delay minutes here, that single category outweighs weather by 17 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 practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 90.8% on time here.
Cancellations sit at 1.31% against a national 1.80%, which is ordinary. Diversions add another 0.24%.
Connections and stage length
What a delay here actually costs
7.2% of arrivals land an hour or more late, close to the national 8.2%. 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 an hour kind, which a normal layover absorbs.
At 304 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 76.2% on time across 5,869 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 5,868 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. February runs 80.3% on time and May 67.5%, a swing of 13 points. If the dates move at all, move them out of May before you think about anything else.
Common questions
PHX to SAN questions
How often is PHX to 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 25.9% of the 5,868 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on PHX to SAN?
Frontier Airlines leads at 75.4% on time across 414 flights. SkyWest Airlines is at the other end on 68.6%, a gap of 7 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 PHX to SAN?
The 5am–8am departure window is the strongest at 90.8% on time. The 8pm–5am window is the weakest at 59.4%, 31 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 May delays on PHX to SAN?
May is the weakest month at 67.5% on time, compared with 80.3% in February. Across the year that is 13 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 PHX — the return legseparate record
- Phoenix Sky Harbor International (PHX) delay statistics
- San Diego International (SAN) delay statistics
- Alaska Airlines on-time record85.4%
- Frontier Airlines on-time record75.4%
- American Airlines on-time record75.0%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. PHX to SAN and SAN to PHX 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, June 2025 to May 2026. Updated monthly. How this data is collected.