Carrier route record

WNPHX→TUS

Southwest Airlines · Phoenix to Tucson

Flights: 236
Period: July 2025 to June 2026
Share of route: 7%
Carriers: 4

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

Southwest on PHX to TUS sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 6 points worse than the national rate of 77.6%. The late ones land roughly 50 minutes behind schedule. That rests on 236 flights. The strongest carrier on the route with a full sample, Envoy Air, flew 570 at 88.9% on time.

The national on-time rate over the same period is 77.6%, so Southwest on PHX to TUS runs 6 points behind the country as a whole. Across a thousand flights that is about 57 extra late arrivals.

On time

71.9%

Arrivals under 15 minutes late, of 235 completed flights

Avg delay

49 min

Across delayed arrivals only, not all flights

Cancelled

0.42%

National rate is 1.81%

Whole route

82.3%

Every carrier on PHX to TUS, 3,395 flights

These figures cover 236 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 TUS

Southwest flew 236 of the 3,395 flights on PHX to TUS, about 7% of it. Its 71.9% on time is 10 points worse than the route as a whole, which runs 82.3%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Envoy at 88.9% to Southwest at 71.9%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. Envoy Air arrives on time 88.9% of the time; SkyWest Airlines manages 81.5%. Sample sizes sit next to every figure, because a two-point gap across 2,251 flights means less than a ten-point one.

On-time performance by carrier on PHX to TUS
Airline	Flights	On time	Avg delay	Cancelled	Grade
Envoy Air	570	88.9%	48 min	0.53%	A+
American Airlinesthin sample	338	83.8%	72 min	1.48%	B
SkyWest Airlines	2,251	81.5%	84 min	0.53%	B+
Southwest Airlines (this page)thin sample	236	71.9%	49 min	0.42%	C+

Envoy leads SkyWest by 7 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 30 points, against 7 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am67 flights89.6%
11am–2pm51 flights82.4%
2pm–5pm—
5pm–8pm8 flights—
8pm–5am110 flights59.6%

Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 59.6% on time, against 89.6% for the 8am–11am 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 110 flights scheduled in it.

Across the year

Southwest on PHX to TUS through the year

Jan–Mar 202654 flights79.2%
Apr–Jun 2026182 flights69.8%

Scale runs 60% to 85%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 71.9% on time across 236 flights.

Split by quarter, Southwest on PHX to TUS logged 54 flights in Jan–Mar 2026 and 182 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 71.9% annual figure is the one to use.

Across the week, Monday is the strongest day at 79.4% on time and Sunday the weakest at 60.6%. 19 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 66% of the 3,213 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
66%
Carrier
33%
National Airspace System
0%

66% 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 3,213 reported delay minutes here, that single category outweighs weather by 66 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 3,213 reported delay minutes.

The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 89.6% on time here.

Cancellations are rare at 0.42%, 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

7.2% 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 109 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 8am–11am window matters as much as it does.

The return leg is a different operation and performs like one: it runs 82.7% on time across 237 flights, 11 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 11 points of difference.

One caution: this is a thin sample. 236 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking Southwest on PHX to TUS

Put together: treat all of this as provisional. 236 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 71.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 235 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