Carrier route record

WNLAX→PHX

Southwest Airlines · Los Angeles to Phoenix

Flights: 2,017
Period: July 2025 to June 2026
Share of route: 27%
Carriers: 7

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

Southwest on LAX to PHX 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 77.6%. The late ones land about 50 minutes behind schedule. That rests on 2,017 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 2,590 at 87.2% on time.

SkyWest Airlines is the most reliable of the three carriers covered here at 87.2% on time across 2,590 flights.

On time

74.9%

Arrivals under 15 minutes late, of 1,995 completed flights

Avg delay

51 min

Across delayed arrivals only, not all flights

Cancelled

1.09%

National rate is 1.81%

Whole route

80.9%

Every carrier on LAX to PHX, 7,608 flights

These figures cover 2,017 flights between July 2025 and June 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

Southwest against every carrier on LAX to PHX

Southwest flew 2,017 of the 7,608 flights on LAX to PHX, about 27% of it. Its 74.9% on time is 6 points worse than the route as a whole, which runs 80.9%. Ranked by on-time rate it is number six of seven carriers on the route, where the range runs from SkyWest at 87.2% to Frontier at 74.6%. 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 87.2% of the time; Frontier Airlines manages 74.6%. Sample sizes sit next to every figure, because a two-point gap across 488 flights means less than a ten-point one.

On-time performance by carrier on LAX to PHX
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	2,590	87.2%	59 min	0.73%	A+
United Airlinesthin sample	339	86.6%	74 min	0.59%	A+
Envoy Airthin sample	6	83.3%	22 min	0.00%	B+
Delta Air Linesthin sample	142	83.0%	77 min	0.70%	B+
American Airlines	2,026	79.1%	91 min	0.49%	B+
Southwest Airlines (this page)	2,017	74.9%	51 min	1.09%	C
Frontier Airlines	488	74.6%	72 min	1.43%	C

The spread between SkyWest and Frontier is 13 points, wide enough that it should decide the booking. On a hundred trips that is 13 more arrivals inside the on-time window.

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 36 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am401 flights91.2%
8am–11am398 flights83.8%
11am–2pm214 flights79.7%
2pm–5pm335 flights65.0%
5pm–8pm321 flights55.7%
8pm–5am348 flights70.3%

Scale runs 45% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 55.7% on time, against 91.2% 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 5am–8am window is the busiest, with 401 flights scheduled in it.

Across the year

Southwest on LAX to PHX through the year

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

June is the worst month at 60.9% on time, 27 points below January, the best at 88.2%. 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. October was the busiest month here, with 181 flights.

Across the week, Saturday is the strongest day at 82.0% on time and Sunday the weakest at 67.2%. 15 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 56% of the 25,000 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
56%
Carrier
29%
National Airspace System
15%
Security
0%

56% 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 25,000 reported delay minutes here, that single category outweighs weather by 56 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 25,482 reported delay minutes.

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 91.2% on time here.

Cancellations sit at 1.09% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

6.6% 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 about 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 72.6% on time across 2,007 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 2,017 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 LAX to PHX

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 88.2% on time and June 60.9%, a swing of 27 points. If the dates move at all, move them out of June before you think about anything else. 1,995 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