Carrier performance at one airport

WN→LAX

Southwest Airlines at Los Angeles International

Departures: 25,511
Period: September 2025 to August 2026
Routes: 25
Rank here: #10 of 10

Southwest Airlines at Los Angeles 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 77.3%. The late ones land about 50 minutes behind schedule. That rests on 25,511 flights, of which SkyWest Airlines flew 40,778 at 84.9% on time.

Measured against the airport rather than the country, Southwest Airlines runs 7 points behind the 79.5% weighted average across all carriers at LAX. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.

On time

72.3%

25,330 completed departures

Avg delay

50 min

Across delayed flights only

Cancelled

0.54%

At LAX, this carrier only

Rank here

#10

Of 10 carriers clearing the floor at LAX

These figures cover 26,000 flights between September 2025 and August 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.

Against the competition

Every carrier at LAX, ranked

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 84.9% of the time; Southwest Airlines manages 72.3%. Sample sizes sit next to every figure, because a two-point gap across 25,511 flights means less than a ten-point one.

On-time performance of all carriers departing LAX
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	40,778	84.9%	70 min	0.62%	B+
United Airlines	29,614	82.5%	62 min	0.50%	B+
Delta Air Lines	37,561	80.9%	68 min	1.16%	B
Alaska Airlines	9,969	80.0%	55 min	0.82%	B+
Spirit Airlines	2,730	76.4%	74 min	2.97%	B
American Airlines	29,810	76.0%	85 min	1.32%	B
JetBlue Airways	7,733	75.7%	68 min	2.66%	B
Hawaiian Airlines	643	74.0%	87 min	1.24%	C
Frontier Airlines	5,699	73.6%	78 min	1.67%	C
Southwest Airlines (this page)	25,511	72.3%	50 min	0.54%	C+

The spread between SkyWest and Southwest 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.

Route by route

Where Southwest Airlines flies from LAX

Southwest Airlines operates 25 routes out of LAX with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.

Southwest Airlines routes from LAX
Route	Flights	On time	Avg delay	Cancelled	Grade
LAX to LAS · Las Vegas	2,360	70.3%	53 min	0.68%	C+
LAX to OAK · Oakland	2,055	79.8%	49 min	0.39%	B+
LAX to PHX · Phoenix	1,992	72.8%	53 min	1.00%	C
LAX to DEN · Denver	1,880	72.2%	55 min	0.48%	C+
LAX to SJC · San Jose	1,871	80.6%	50 min	0.91%	B+
LAX to SMF · Sacramento	1,650	79.0%	54 min	0.24%	B+
LAX to DAL · Dallas	1,482	63.1%	43 min	0.74%	D+
LAX to SFO · San Francisco	1,473	50.7%	62 min	0.34%	F+
LAX to MDW · Chicago	1,283	76.7%	44 min	0.55%	B+
LAX to HOU · Houston	1,194	69.4%	43 min	0.17%	C+
LAX to AUS · Austin	1,036	66.2%	48 min	0.48%	C+
LAX to BWI · Baltimore	1,022	76.2%	38 min	1.08%	B
LAX to BNA · Nashville	921	77.2%	37 min	0.65%	B+
LAX to STL · St. Louis	674	74.9%	48 min	0.30%	C+
LAX to MCI · Kansas City	560	71.2%	54 min	0.89%	C+
LAX to ELP · El Paso	527	74.3%	50 min	0.00%	C+
LAX to HNL · Honolulu	516	75.5%	47 min	0.19%	B+
LAX to ABQ · Albuquerque	515	79.8%	41 min	0.19%	B+
LAX to TUS · Tucson	492	63.7%	50 min	0.20%	D+
LAX to SLC · Salt Lake City	371	79.7%	47 min	0.27%	B+
LAX to MCO · Orlando	365	74.5%	33 min	0.00%	C+
LAX to MSY · New Orleansthin sample	356	69.9%	44 min	0.28%	C+
LAX to SAT · San Antoniothin sample	337	65.0%	40 min	0.00%	C+
LAX to RNO · Renothin sample	321	74.8%	47 min	1.25%	C
LAX to TPA · Tampathin sample	177	61.4%	48 min	0.00%	D+

Departure window

Best time of day for this operation

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.

5am–8am5,374 flights92.6%
8am–11am4,690 flights78.2%
11am–2pm4,233 flights67.8%
2pm–5pm3,686 flights63.1%
5pm–8pm3,704 flights56.9%
8pm–5am3,824 flights65.7%

Scale runs 50% to 100%.

The 5pm–8pm window is where this operation falls apart: 56.9% on time, against 92.6% 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 5,374 flights scheduled in it.

Across the year

Seasonal pattern

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

June is the worst month at 58.6% on time, 25 points below January, 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. July was the busiest month here, with 2,313 flights.

Delay causes

What holds this operation up

Late-arriving aircraft
51%
Carrier
29%
National Airspace System
19%
Extreme weather
0%
Security
0%

51% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 347,000 reported delay minutes here, that single category outweighs weather by 51 to one. The split is drawn from 346,592 reported delay minutes.

Cancellations are rare at 0.54%, 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.

7.0% of arrivals land an hour or more late, close to the national 8.3%, so 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.

25,511 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 83.2% on time and June 58.6%, a swing of 25 points. If the dates move at all, move them out of June before you think about anything else. 25,330 completed flights over 12 months sit behind that.

Common questions

Southwest Airlines at LAX

How often is Southwest Airlines at LAX delayed?

Roughly one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 27.7% of the 25,511 flights in this analysis, against 22.7% nationally. Delayed flights are late by about 50 minutes on average.

Which airline is most reliable on Southwest Airlines at LAX?

SkyWest Airlines leads at 84.9% on time across 40,778 flights. Southwest Airlines is at the other end on 72.3%, a gap of 13 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 Southwest Airlines at LAX?

The 5am–8am departure window is the strongest at 92.6% on time. The 5pm–8pm window is the weakest at 56.9%, 36 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 Southwest Airlines at LAX?

June is the weakest month at 58.6% on time, compared with 83.2% in January. Across the year that is 25 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures