Carrier performance at one airport

WN→PHX

Southwest Airlines at Phoenix Sky Harbor International

Departures: 67,877
Period: June 2025 to May 2026
Routes: 25
Rank here: #8 of 9

Southwest Airlines at Phoenix sits in the middle of the pack with a B+. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.4%. The late ones land about 50 minutes behind schedule. That rests on 67,877 flights, of which Delta Air Lines flew 10,708 at 86.6% on time.

Measured against the airport rather than the country, Southwest Airlines runs 4 points behind the 79.1% weighted average across all carriers at PHX. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.

On time

75.1%

67,290 completed departures

Avg delay

49 min

Across delayed flights only

Cancelled

0.65%

At PHX, this carrier only

Rank here

Of 9 carriers clearing the floor at PHX

These figures cover 68,000 flights between June 2025 and May 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 PHX, ranked

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 86.6% of the time; JetBlue Airways manages 70.6%. Sample sizes sit next to every figure, because a two-point gap across 1,139 flights means less than a ten-point one.

On-time performance of all carriers departing PHX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	10,708	86.6%	84 min	1.06%	A
Envoy Air	9,964	85.3%	49 min	0.70%	A+
Alaska Airlines	5,615	85.1%	56 min	0.68%	A+
United Airlines	10,185	81.5%	77 min	0.79%	B+
SkyWest Airlines	27,166	81.3%	78 min	0.80%	B+
American Airlines	56,179	79.4%	70 min	1.13%	B
Frontier Airlines	7,555	79.0%	84 min	1.28%	B
Southwest Airlines (this page)	67,877	75.1%	49 min	0.65%	B+
JetBlue Airways	1,139	70.6%	68 min	2.37%	C

The spread between Delta and JetBlue is 16 points, wide enough that it should decide the booking. On a hundred trips that is 16 more arrivals inside the on-time window.

Route by route

Where Southwest Airlines flies from PHX

Southwest Airlines operates 25 routes out of PHX 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 PHX
Route	Flights	On time	Avg delay	Cancelled	Grade
PHX to DEN · Denver	3,938	72.6%	57 min	1.09%	C
PHX to LAS · Las Vegas	3,448	77.9%	51 min	1.04%	B
PHX to SAN · San Diego	3,189	73.4%	50 min	1.07%	C
PHX to DAL · Dallas	2,892	77.2%	52 min	1.94%	B
PHX to MDW · Chicago	2,679	74.4%	47 min	1.12%	C
PHX to SNA · Santa Ana	2,425	79.7%	43 min	0.41%	B+
PHX to BUR · Burbank	2,176	80.2%	55 min	0.87%	B+
PHX to SMF · Sacramento	2,169	79.3%	47 min	0.37%	B+
PHX to HOU · Houston	2,160	72.0%	48 min	0.51%	C+
PHX to LAX · Los Angeles	2,033	74.0%	48 min	0.44%	C+
PHX to AUS · Austin	1,983	75.6%	49 min	0.61%	B+
PHX to OAK · Oakland	1,948	76.0%	49 min	0.36%	B+
PHX to SJC · San Jose	1,884	78.6%	47 min	0.37%	B+
PHX to ABQ · Albuquerque	1,880	77.8%	50 min	0.27%	B+
PHX to SLC · Salt Lake City	1,857	76.2%	48 min	0.43%	B+
PHX to BNA · Nashville	1,818	75.7%	46 min	0.50%	B+
PHX to MCI · Kansas City	1,632	74.9%	52 min	0.61%	C+
PHX to ONT · Ontario	1,608	75.1%	50 min	0.19%	B+
PHX to STL · St. Louis	1,601	77.7%	47 min	0.19%	B+
PHX to LGB · Long Beach	1,537	80.6%	45 min	0.46%	B+
PHX to SAT · San Antonio	1,385	74.9%	48 min	0.22%	C+
PHX to BWI · Baltimore	1,311	80.1%	44 min	1.07%	B
PHX to PDX · Portland	1,277	70.5%	46 min	0.47%	C+
PHX to ELP · El Paso	1,216	76.4%	48 min	0.66%	B+
PHX to OMA · Omaha	1,215	74.8%	53 min	0.58%	C+

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 31 points, against 16 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am8,569 flights93.7%
8am–11am15,741 flights85.0%
11am–2pm10,747 flights76.3%
2pm–5pm11,901 flights67.9%
5pm–8pm11,580 flights63.1%
8pm–5am9,339 flights64.1%

Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 63.1% on time, against 93.7% 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.

Across the year

Seasonal pattern

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

Delays peak in May, when the on-time rate falls to 67.4%. January is the strongest month at 83.4%. Moving a flexible trip across that boundary buys 16 points.

Delay causes

What holds this operation up

Late-arriving aircraft
49%
Carrier
36%
National Airspace System
14%
Extreme weather
1%
Security
0%

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 824,000 reported delay minutes here, that single category outweighs weather by 41 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.

Cancellations are rare at 0.65%, below the national 1.80% 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.

6.0% of arrivals land an hour or more late, close to the national 8.2%. 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 are the about 50 minutes kind, which a normal layover absorbs.

67,877 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 83.4% on time and May 67.4%, a swing of 16 points. If the dates move at all, move them out of May before you think about anything else.

Common questions

Southwest Airlines at PHX

How often is Southwest Airlines at PHX delayed?

About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 24.9% of the 67,877 flights in this analysis, against 22.6% nationally. Delayed flights are late by about 50 minutes on average.

Which airline is most reliable on Southwest Airlines at PHX?

Delta Air Lines leads at 86.6% on time across 10,708 flights. JetBlue Airways is at the other end on 70.6%, a gap of 16 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 PHX?

The 5am–8am departure window is the strongest at 93.7% on time. The 5pm–8pm window is the weakest at 63.1%, 31 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 May delays on Southwest Airlines at PHX?

May is the weakest month at 67.4% on time, compared with 83.4% in January. Across the year that is 16 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, June 2025 to May 2026. Updated monthly. How this data is collected.

Key figures