Carrier route record
WNLAS→PHX
Southwest Airlines · Las Vegas to Phoenix
- Flights
- 3,446
- Period
- July 2025 to June 2026
- Share of route
- 57%
- Carriers
- 6
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on LAS to PHX lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by roughly 55 minutes on average. That is a workable record, not a spotless one. That rests on 3,446 flights. The strongest carrier on the route with a full sample, American Airlines, flew 1,688 at 81.0% on time.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on LAS to PHX from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.4%
Arrivals under 15 minutes late, of 3,408 completed flights
Avg delay
53 min
Across delayed arrivals only, not all flights
Cancelled
1.04%
National rate is 1.81%
Whole route
78.2%
Every carrier on LAS to PHX, 6,025 flights
These figures cover 3,446 flights between July 2025 and June 2026. The median arrival is 5 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 LAS to PHX
Southwest flew 3,446 of the 6,025 flights on LAS to PHX, most of the route. Its 76.4% on time is 2 points worse than the route as a whole, which runs 78.2%. Ranked by on-time rate it is last of six carriers on the route, where the range runs from Spirit at 100.0% to Southwest at 76.4%. Three of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: 2 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 4 | 100.0% | — | 0.00% | A+ |
| Envoy Airthin sample | 6 | 100.0% | — | 0.00% | A+ |
| SkyWest Airlinesthin sample | 16 | 81.2% | 53 min | 0.00% | B+ |
| American Airlines | 1,688 | 81.0% | 78 min | 0.83% | B+ |
| Frontier Airlines | 865 | 79.5% | 95 min | 1.16% | B |
| Southwest Airlines (this page) | 3,446 | 76.4% | 53 min | 1.04% | B |
No carrier stands out. American tops the table at 81.0%, 2 points clear of the bottom, which is inside the range this kind of sample moves year to year.
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 31 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am668 flights94.7%
- 8am–11am573 flights86.0%
- 11am–2pm518 flights78.4%
- 2pm–5pm654 flights65.9%
- 5pm–8pm569 flights63.3%
- 8pm–5am464 flights66.3%
Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 63.3% on time, against 94.7% 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. The 5am–8am window is the busiest, with 668 flights scheduled in it.
Across the year
Southwest on LAS to PHX through the year
June is the worst month at 67.3% on time, 19 points below January, the best at 86.1%. 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. May was the busiest month here, with 316 flights.
Across the week, Saturday is the strongest day at 86.4% on time and Thursday the weakest at 68.6%. 18 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 52% of the 42,000 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.
- 52%Late-arriving aircraft
- 31%Carrier
- 15%National Airspace System
- 2%Extreme weather
- 0%Security
52% 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 42,000 reported delay minutes here, that single category outweighs weather by 31 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 42,404 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 94.7% on time here.
Cancellations sit at 1.04% against a national 1.81%, which is ordinary. Diversions add another 0.06%.
Connections and stage length
What a delay here costs
6.7% 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 55 minutes, which a normal layover absorbs.
At 255 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 77.3% on time across 3,447 flights, within about a point 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 3,446 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 LAS to PHX
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 86.1% on time and June 67.3%, a swing of 19 points. If the dates move at all, move them out of June before you think about anything else. 3,408 completed flights over 12 months sit behind that.
Related
Where to go next
- LAS to PHX, every carrier
- Southwest on PHX to LAS, the return leg
- American Airlines on LAS to PHX81.0%
- Frontier Airlines on LAS to PHX79.5%
- Southwest Airlines network-wide record
- Harry Reid International (LAS) delay statistics
- Phoenix Sky Harbor International (PHX) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.