Carrier route record

WNPHX→LAX

Southwest Airlines · Phoenix to Los Angeles

Flights: 2,007
Period: July 2025 to June 2026
Share of route: 26%
Carriers: 7

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

Southwest on PHX to LAX sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 5 points worse than the national rate of 77.6%. The late ones land roughly 50 minutes behind schedule. That rests on 2,007 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 2,590 at 90.2% on time.

SkyWest Airlines is the most reliable of the three carriers covered here at 90.2% on time across 2,590 flights.

On time

72.6%

Arrivals under 15 minutes late, of 1,996 completed flights

Avg delay

49 min

Across delayed arrivals only, not all flights

Cancelled

0.55%

National rate is 1.81%

Whole route

82.8%

Every carrier on PHX to LAX, 7,598 flights

These figures cover 2,007 flights between July 2025 and June 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.

Carrier by carrier

Southwest against every carrier on PHX to LAX

Southwest flew 2,007 of the 7,598 flights on PHX to LAX, about 26% of it. Its 72.6% on time is 10 points worse than the route as a whole, which runs 82.8%. Ranked by on-time rate it is last of seven carriers on the route, where the range runs from Envoy at 100.0% to Southwest at 72.6%. Three of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 90.2% of the time; American Airlines manages 81.7%. Sample sizes sit next to every figure, because a two-point gap across 2,026 flights means less than a ten-point one.

On-time performance by carrier on PHX to LAX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Envoy Airthin sample	5	100.0%	—	0.00%	A+
Delta Air Linesthin sample	142	95.0%	185 min	0.70%	A+
SkyWest Airlines	2,590	90.2%	67 min	0.73%	A+
United Airlinesthin sample	339	87.8%	104 min	0.59%	A+
Frontier Airlines	489	83.1%	86 min	1.02%	B
American Airlines	2,026	81.7%	63 min	0.54%	B+
Southwest Airlines (this page)	2,007	72.6%	49 min	0.55%	C+

SkyWest leads American by 9 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

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 39 points, against 9 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am230 flights95.2%
8am–11am358 flights88.4%
11am–2pm311 flights77.7%
2pm–5pm379 flights69.4%
5pm–8pm257 flights55.9%
8pm–5am472 flights57.9%

Scale runs 45% to 100%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 55.9% on time, against 95.2% 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 8pm–5am window is the busiest, with 472 flights scheduled in it.

Across the year

Southwest on PHX to LAX through the year

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

June is the worst month at 52.5% on time, 30 points below January, the best at 82.3%. 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 181 flights.

Across the week, Tuesday is the strongest day at 80.5% on time and Sunday the weakest at 59.8%. 21 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 49% of the 27,000 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
49%
Carrier
40%
National Airspace System
8%
Extreme weather
1%
Security
1%

49% 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 27,000 reported delay minutes here, that single category outweighs weather by 36 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 26,563 reported delay minutes.

The largest share of delay minutes, 40%, 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 27,000 delay minutes reported here.

Cancellations are rare at 0.55%, 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

6.5% 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 50 minutes, which a normal layover absorbs.

At 370 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 74.9% on time across 2,017 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 2,007 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 LAX

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 82.3% on time and June 52.5%, a swing of 30 points. If the dates move at all, move them out of June before you think about anything else. 1,996 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