Carrier route record

WNPHX→SMF

Southwest Airlines · Phoenix to Sacramento

Flights: 2,149
Period: July 2025 to June 2026
Share of route: 59%
Carriers: 4

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.

Southwest on PHX to SMF lands a B+, about a point better than the national rate of 77.6%. About one flight in five arrives 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 2,149 flights, with a median arrival 5 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate Southwest on PHX to SMF from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

78.9%

Arrivals under 15 minutes late, of 2,140 completed flights

Avg delay

47 min

Across delayed arrivals only, not all flights

Cancelled

0.33%

National rate is 1.81%

Whole route

80.2%

Every carrier on PHX to SMF, 3,673 flights

These figures cover 2,149 flights between July 2025 and June 2026. The median arrival is 5 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

Southwest against every carrier on PHX to SMF

Southwest flew 2,149 of the 3,673 flights on PHX to SMF, most of the route. Its 78.9% on time is about level with the route as a whole at 80.2%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Envoy at 85.5% to Southwest at 78.9%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

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.

On-time performance by carrier on PHX to SMF
Airline	Flights	On time	Avg delay	Cancelled	Grade
Envoy Airthin sample	112	85.5%	51 min	0.89%	A+
American Airlines	1,079	82.4%	64 min	0.46%	B+
SkyWest Airlinesthin sample	333	80.1%	60 min	0.30%	B+
Southwest Airlines (this page)	2,149	78.9%	47 min	0.33%	B+

Departure window

When Southwest runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 42 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–8am372 flights98.9%
8am–11am423 flights91.9%
11am–2pm272 flights79.6%
2pm–5pm346 flights77.4%
5pm–8pm351 flights67.1%
8pm–5am385 flights56.9%

Scale runs 50% to 100%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 56.9% on time, against 98.9% 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 423 flights scheduled in it.

Across the year

Southwest on PHX to SMF through the year

Darker means more delays. Figures are on-time percentages.January best, June worst

June is the worst month at 67.7% on time, 19 points below January, the best at 87.0%. 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 207 flights.

Across the week, Wednesday is the strongest day at 83.2% on time and Sunday the weakest at 73.2%. 10 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Southwest runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 55% of the 21,000 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
55%
Carrier
41%
National Airspace System
3%
Extreme weather
0%
Security
0%

55% 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 21,000 reported delay minutes here, that single category outweighs weather by 55 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 21,431 reported delay minutes.

The largest share of delay minutes, 41%, 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 8,718 of the 21,000 delay minutes reported here.

Cancellations are rare at 0.33%, 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 costs

5.1% 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 roughly 45 minutes, which a normal layover absorbs.

The 647 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 79.0% on time across 2,147 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 2,149 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 Southwest on PHX to SMF

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 87.0% on time and June 67.7%, a swing of 19 points. If the dates move at all, move them out of June before you think about anything else. 2,140 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures