Route reliability record
PHX→SFO
Phoenix to San Francisco
- Flights
- 4,728
- Period
- September 2025 to August 2026
- Distance
- 651 mi
- Carriers
- 6
This route draws a D+. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 4,728 PHX to SFO flights, of which United Airlines flew 1,489 at 67.7% on time.
Best time to fly PHX to SFO: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 68.2% of the time and Saturday flights 73.5%, against 63.6% for the route overall.
United Airlines is the most reliable of the four carriers covered here at 67.7% on time across 1,489 flights.
Key figures
On time
63.6%
Arrivals under 15 minutes late, of 4,699 completed flights
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
0.57%
National rate is 1.89%
Best carrier
United
67.7% on time across 1,489 flights
These figures cover 4,728 flights between September 2025 and August 2026. Beyond the headline rate, 13.2% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on PHX to SFO
The choice of carrier is not cosmetic here. United Airlines arrives on time 67.7% of the time; Southwest Airlines manages 57.7%. Sample sizes sit next to every figure, because a two-point gap across 1,076 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Envoy Airthin sample | 1 | 100.0% | — | 0.00% | A+ |
| United Airlines | 1,489 | 67.7% | 59 min | 0.47% | C+ |
| Frontier Airlinesthin sample | 278 | 65.8% | 64 min | 1.08% | C |
| SkyWest Airlines | 572 | 63.7% | 67 min | 0.17% | D+ |
| American Airlines | 1,312 | 63.2% | 77 min | 0.91% | D+ |
| Southwest Airlines | 1,076 | 57.7% | 56 min | 0.37% | D+ |
United leads Southwest by 10 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Phoenix to San Francisco
Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 3 of the top 5 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. PHX → SJCPhoenix to San Jose | Southwest Airlines | 76.6% | 76.9% | 0.38% | 5am–8am, Tue | — |
| 2. PHX → SJCPhoenix to San Jose | American Airlines | 75.9% | 76.6% | 0.88% | 11am–2pm, Wed | — |
| 3. PHX → OAKPhoenix to Oakland | Southwest Airlines | 75.3% | 75.6% | 0.42% | 5am–8am, Sat | — |
| 4. PHX → SFOPhoenix to San Francisco | United Airlines | 67.4% | 67.7% | 0.47% | 2pm–5pm, Tue | — |
| 5. PHX → SFOPhoenix to San Francisco | SkyWest Airlines | 63.6% | 63.7% | 0.17% | 8am–11am, Sat | — |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
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 10 points between the best and worst carrier.
- 5am–8am661 flights68.2%
- 8am–11am1,032 flights65.9%
- 11am–2pm675 flights60.2%
- 2pm–5pm884 flights67.7%
- 5pm–8pm905 flights62.1%
- 8pm–5am571 flights54.2%
Scale runs 45% to 75%.
The 8pm–5am window is where this operation falls apart: 54.2% on time, against 68.2% 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. The 8am–11am window is the busiest, with 1,032 flights scheduled in it.
Explore
Filter PHX to SFO by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On PHX to SFO, the best departure window is 5am–8am at 68.2% on time and the worst is 8pm–5am at 54.2%, a wide gap of 14.0 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am68.2%
- 8–11am65.9%
- 11am–2pm60.2%
- 2–5pm67.7%
- 5–8pm62.1%
- 8pm–5am54.2%
best all US flightsScale 45% to 95%.
Across the year
When delays peak on this route
This route's year swings by 46 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.
June is the worst month at 37.3% on time, 46 points below March, the best at 83.2%. 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. March was the busiest month here, with 454 flights.
Across the week, Saturday is the strongest day at 73.5% on time and Monday the weakest at 56.9%, a spread of 17 points.
Delay causes
Why this route gets delayed
National Airspace System accounts for 43% of the 110,000 delay minutes carriers reported here, and the remaining four split what is left.
- 43%National Airspace System
- 35%Late-arriving aircraft
- 20%Carrier
- 2%Extreme weather
- 0%Security
35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 110,000 reported delay minutes here, that single category outweighs weather by 17 to one. The split is drawn from 110,144 reported delay minutes.
43% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 47,000 minutes out of 110,000, against a national NAS share of 21%.
Cancellations are rare at 0.57%, below the national 1.89% 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
13.2% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
The 651 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.
The return leg is a different operation and performs like one: it runs 72.8% on time across 4,727 flights, 9 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 9 points of difference.
The sample behind these figures is 4,728 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.
Work out the risk of missing a connection in SFO after this flight
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 83.2% on time and June 37.3%, a swing of 46 points. If the dates move at all, move them out of June before you think about anything else. 4,699 completed flights over 12 months sit behind that.
Common questions
PHX to SFO questions
How often is PHX to SFO delayed?
Roughly one flight in three arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 36.4% of the 4,728 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on PHX to SFO?
United Airlines leads at 67.7% on time across 1,489 flights. Southwest Airlines is at the other end on 57.7%, a gap of 10 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 SFO?
The 5am–8am departure window is the strongest at 68.2% on time. The 8pm–5am window is the weakest at 54.2%, 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 June delays on PHX to SFO?
June is the weakest month at 37.3% on time, compared with 83.2% in March. Across the year that is 46 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
- SFO to PHX — the return legseparate record
- Phoenix Sky Harbor International (PHX) delay statistics
- San Francisco International (SFO) delay statistics
- United Airlines on PHX to SFO67.7%
- Frontier Airlines on PHX to SFO65.8%
- SkyWest Airlines on PHX to SFO63.7%
- American Airlines on PHX to SFO63.2%
- Southwest Airlines on PHX to SFO57.7%
- PHX to DEN, a related route76.7%
- LAX to SFO, a related route60.1%
- PHX to LAX, a related route82.1%
- Envoy Air on-time record100.0%
- United Airlines on-time record67.7%
- Frontier Airlines on-time record65.8%
- Same route, different airline: where the carrier you pick matters most
- Why the first flight of the morning is statistically safest
Direction matters. PHX to SFO and SFO to PHX are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed PHX to SFO’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.