Skip to content
DelayAtlas

Route reliability record

PHXSBP

Phoenix to San Luis Obispo

Flights
1,231
Period
July 2025 to June 2026
Distance
509 mi
Carriers
3
B+GRADE

This route lands a B+, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 1,231 PHX to SBP flights, of which American Airlines flew 533 at 81.4% on time.

Best time to fly PHX to SBP: a 11am–2pm departure, ideally on a Tuesday. Flights in that window arrived on time 92.0% of the time and Tuesday flights 92.0%, against 83.1% for the route overall.

Set against the rest of the country, this route's record is 6 points better than the US average of 77.6%. That gap is worth roughly 55 fewer late arrivals for every thousand flights.

Key figures

On time

83.1%

Arrivals under 15 minutes late, of 1,213 completed flights

Avg delay

69 min

Across delayed arrivals only, not all flights

Cancelled

0.81%

National rate is 1.81%

Best carrier

American

81.4% on time across 533 flights

These figures cover 1,231 flights between July 2025 and June 2026. The median arrival is 8 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 SBP

The two carriers here are closely matched: 3 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on PHX to SBP
AirlineFlightsOn timeAvg delayCancelledGrade
Envoy Airthin sample28193.1%41 min1.07%A
American Airlines53381.4%81 min0.56%B+
SkyWest Airlines41778.5%63 min0.96%B+

No carrier stands out. American tops the table at 81.4%, 3 points clear of the bottom, which is inside the range this kind of sample moves year to year.

Best ways to make this trip

The most reliable ways to fly Phoenix to San Luis Obispo

Every airline on this route, ranked by how often a scheduled flight actually operated and arrived on time, with its best departure time and most punctual flight number. No nearby airport pair beat these.

Most reliable ways to fly from PHX to SBP
OptionAirlineSuccessOn timeCancelledBest departureMost punctual flight
1. PHXSBPPhoenix to San Luis ObispoAmerican Airlines80.9%81.4%0.56%11am–2pm, Tue
2. PHXSBPPhoenix to San Luis ObispoSkyWest Airlines77.7%78.5%0.96%8am–11am, Tue

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.

Plan this trip by month, day and time

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 22 points, against 3 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

  • 5am–8am5 flights
  • 8am–11am334 flights88.5%
  • 11am–2pm125 flights92.0%
  • 2pm–5pm346 flights83.1%
  • 5pm–8pm210 flights81.6%
  • 8pm–5am211 flights70.0%

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

The best window here is not the first bank but the 11am–2pm slot at 92.0% on time, ahead of 8pm–5am at 70.0%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 2pm–5pm window is the busiest, with 346 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 20 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.

On-time rate by calendar month84J85F78M86A82M89J69J87A85S76O86N87D
Darker means more delays. Figures are on-time percentages.June best, July worst

July is the worst month at 69.2% on time, 20 points below June, the best at 88.9%. 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. December was the busiest month here, with 138 flights.

Across the week, Tuesday is the strongest day at 92.0% on time and Thursday the weakest at 77.7%. 14 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week82.5Mon92.0Tue83.4Wed77.7Thu85.5Fri83.4Sat78.4Sun
Monday: 82.5 percent on time. Tuesday: 92.0 percent on time. Wednesday: 83.4 percent on time. Thursday: 77.7 percent on time. Friday: 85.5 percent on time. Saturday: 83.4 percent on time. Sunday: 78.4 percent on time

Delay causes

Why this route gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 46% of the 14,000 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.

  • Late-arriving aircraft
    46%
  • Carrier
    46%
  • National Airspace System
    7%
  • Extreme weather
    1%

46% 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 14,000 reported delay minutes here, that single category outweighs weather by 46 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 14,225 reported delay minutes.

The largest share of delay minutes, 46%, 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 6,583 of the 14,000 delay minutes reported here.

Cancellations are rare at 0.81%, 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

5.7% 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 last a little over an hour, which a normal layover absorbs.

The 509 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg runs 82.9% on time across 1,230 flights, within half a point 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 1,231 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 SBP 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. June runs 88.9% on time and July 69.2%, a swing of 20 points. If the dates move at all, move them out of July before you think about anything else. 1,213 completed flights over 12 months sit behind that.

Common questions

PHX to SBP questions

How often is PHX to SBP delayed?

About one flight in six arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 16.9% of the 1,231 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.

Which airline is most reliable on PHX to SBP?

American Airlines leads at 81.4% on time across 533 flights. SkyWest Airlines is at the other end on 78.5%, a gap of 3 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 SBP?

The 11am–2pm departure window is the strongest at 92.0% on time. The 8pm–5am window is the weakest at 70.0%, 22 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 PHX to SBP?

July is the weakest month at 69.2% on time, compared with 88.9% in June. Across the year that is 20 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

Direction matters. PHX to SBP and SBP to PHX are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Embed PHX to SBP’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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.