Carrier performance at one airport

WN→PHX

Southwest Airlines at Phoenix Sky Harbor International

Departures: 66,973
Period: September 2025 to August 2026
Routes: 25
Rank here: #8 of 9

Southwest Airlines at Phoenix sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.3%. The late ones land roughly 50 minutes behind schedule. That rests on 66,973 flights, of which Delta Air Lines flew 10,637 at 86.1% on time.

Measured against the airport rather than the country, Southwest Airlines runs 5 points behind the 77.9% 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

73.2%

66,426 completed departures

Avg delay

49 min

Across delayed flights only

Cancelled

0.61%

At PHX, this carrier only

Rank here

Of 9 carriers clearing the floor at PHX

These figures cover 67,000 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 PHX, ranked

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 86.1% of the time; JetBlue Airways manages 70.2%. Sample sizes sit next to every figure, because a two-point gap across 1,102 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	10,637	86.1%	86 min	1.14%	A
Alaska Airlines	5,685	84.9%	54 min	0.62%	B+
Envoy Air	11,150	84.0%	50 min	0.61%	B+
SkyWest Airlines	27,507	80.3%	78 min	0.84%	B+
United Airlines	10,074	80.3%	77 min	0.78%	B+
Frontier Airlines	7,636	78.9%	82 min	1.18%	B
American Airlines	56,697	78.5%	71 min	1.13%	B
Southwest Airlines (this page)	66,973	73.2%	49 min	0.61%	C+
JetBlue Airways	1,102	70.2%	77 min	3.27%	C−

JetBlue Airways cancels 3.3% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.

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	3,934	72.1%	56 min	0.66%	C+
PHX to LAS · Las Vegas	3,466	76.9%	52 min	1.13%	B
PHX to SAN · San Diego	3,236	67.4%	48 min	0.96%	C+
PHX to DAL · Dallas	2,906	75.4%	51 min	1.48%	B
PHX to MDW · Chicago	2,633	70.9%	47 min	1.06%	C
PHX to SNA · Santa Ana	2,412	78.7%	45 min	0.41%	B+
PHX to BUR · Burbank	2,191	79.1%	55 min	0.73%	B+
PHX to HOU · Houston	2,124	71.4%	47 min	0.47%	C+
PHX to SMF · Sacramento	2,118	78.8%	47 min	0.33%	B+
PHX to LAX · Los Angeles	1,958	70.4%	46 min	0.51%	C+
PHX to AUS · Austin	1,950	73.4%	48 min	0.51%	C+
PHX to OAK · Oakland	1,922	75.6%	48 min	0.42%	B+
PHX to ABQ · Albuquerque	1,888	74.0%	49 min	0.21%	C+
PHX to SLC · Salt Lake City	1,856	76.0%	49 min	0.27%	B+
PHX to SJC · San Jose	1,837	76.9%	48 min	0.38%	B+
PHX to BNA · Nashville	1,763	72.1%	44 min	0.51%	C+
PHX to MCI · Kansas City	1,645	74.3%	49 min	0.43%	C+
PHX to STL · St. Louis	1,632	75.1%	47 min	0.12%	B+
PHX to ONT · Ontario	1,616	73.9%	49 min	0.25%	C+
PHX to LGB · Long Beach	1,516	79.2%	42 min	0.53%	B+
PHX to SAT · San Antonio	1,382	74.1%	50 min	0.22%	C+
PHX to PDX · Portland	1,268	67.6%	46 min	0.55%	C+
PHX to BWI · Baltimore	1,220	78.5%	45 min	0.90%	B+
PHX to OMA · Omaha	1,218	73.4%	53 min	0.57%	C+
PHX to ELP · El Paso	1,202	71.1%	48 min	0.83%	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 35 points, against 16 points between the best and worst carrier.

5am–8am8,093 flights94.1%
8am–11am15,817 flights84.1%
11am–2pm10,741 flights74.4%
2pm–5pm11,590 flights65.9%
5pm–8pm11,269 flights59.5%
8pm–5am9,463 flights60.9%

Scale runs 50% to 100%.

The 5pm–8pm window is where this operation falls apart: 59.5% on time, against 94.1% 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 15,817 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 63.2% on time, 20 points below January, the best at 83.4%. 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. March was the busiest month here, with 6,343 flights.

Delay causes

What holds this operation up

Late-arriving aircraft
50%
Carrier
35%
National Airspace System
14%
Extreme weather
2%
Security
0%

50% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 870,000 reported delay minutes here, that single category outweighs weather by 33 to one. The split is drawn from 870,015 reported delay minutes.

Cancellations are rare at 0.61%, 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.

6.5% 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 roughly 50 minutes, which a normal layover absorbs.

66,973 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 June 63.2%, a swing of 20 points. If the dates move at all, move them out of June before you think about anything else. 66,426 completed flights over 12 months sit behind that.

Common questions

Southwest Airlines at PHX

How often is Southwest Airlines at PHX delayed?

About 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 26.8% of the 66,973 flights in this analysis, against 22.7% nationally. Delayed flights are late by roughly 50 minutes on average.

Which airline is most reliable on Southwest Airlines at PHX?

Delta Air Lines leads at 86.1% on time across 10,637 flights. JetBlue Airways is at the other end on 70.2%, 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 94.1% on time. The 5pm–8pm window is the weakest at 59.5%, 35 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 PHX?

June is the weakest month at 63.2% on time, compared with 83.4% in January. Across the year that is 20 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