Carrier route record
WNPDX→LAS
Southwest Airlines · Portland to Las Vegas
- Flights
- 1,149
- Period
- July 2025 to June 2026
- Share of route
- 39%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on PDX to LAS lands a B+, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by about 45 minutes on average. That is a workable record, not a spotless one. That rests on 1,149 flights, with a median arrival 1 minute early.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on PDX to LAS from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
77.2%
Arrivals under 15 minutes late, of 1,145 completed flights
Avg delay
46 min
Across delayed arrivals only, not all flights
Cancelled
0.17%
National rate is 1.81%
Whole route
80.2%
Every carrier on PDX to LAS, 2,983 flights
These figures cover 1,149 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 PDX to LAS
Southwest flew 1,149 of the 2,983 flights on PDX to LAS, about 39% of it. Its 77.2% on time is 3 points worse than the route as a whole, which runs 80.2%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Spirit at 86.6% to Frontier at 72.3%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 128 | 86.6% | 90 min | 0.00% | A+ |
| Alaska Airlines | 1,534 | 82.7% | 51 min | 0.52% | B+ |
| Southwest Airlines (this page) | 1,149 | 77.2% | 46 min | 0.17% | B+ |
| Frontier Airlinesthin sample | 172 | 72.3% | 101 min | 3.49% | C− |
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 48 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am363 flights97.2%
- 8am–11am242 flights75.0%
- 11am–2pm143 flights77.6%
- 2pm–5pm200 flights69.3%
- 5pm–8pm183 flights49.5%
- 8pm–5am18 flights—
Scale runs 40% to 100%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 49.5% on time, against 97.2% 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 363 flights scheduled in it.
Across the year
Southwest on PDX to LAS through the year
June is the worst month at 69.4% on time, 23 points below January, the best at 92.5%. 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 115 flights.
Across the week, Tuesday is the strongest day at 89.2% on time and Thursday the weakest at 70.1%. 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 56% of the 12,000 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.
- 56%Late-arriving aircraft
- 27%Carrier
- 17%National Airspace System
56% 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 12,000 reported delay minutes here, that single category outweighs weather by 56 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 11,892 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 97.2% on time here.
Cancellations are rare at 0.17%, 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
Badly late arrivals are rare here: only 4.8% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
The 763 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 72.3% on time across 1,149 flights, 5 points below 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 5 points of difference.
The sample behind these figures is 1,149 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 PDX to LAS
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 92.5% on time and June 69.4%, a swing of 23 points. If the dates move at all, move them out of June before you think about anything else. 1,145 completed flights over 12 months sit behind that.
Related
Where to go next
- PDX to LAS, every carrier
- Southwest on LAS to PDX, the return leg
- Spirit Airlines on PDX to LAS86.6%
- Alaska Airlines on PDX to LAS82.7%
- Frontier Airlines on PDX to LAS72.3%
- Southwest Airlines network-wide record
- Portland International (PDX) delay statistics
- Harry Reid International (LAS) 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.