Route reliability record

LAS→PDX

Las Vegas to Portland

Flights: 2,984
Period: July 2025 to June 2026
Distance: 763 mi
Carriers: 4

This route lands a B+, about a point better than the national rate of 77.6%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 2,984 flights, of which Alaska Airlines flew 1,534 at 83.2% on time.

The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

78.8%

Arrivals under 15 minutes late, of 2,964 completed flights

Avg delay

56 min

Across delayed arrivals only, not all flights

Cancelled

0.60%

National rate is 1.81%

Best carrier

Alaska

83.2% on time across 1,534 flights

These figures cover 2,984 flights between July 2025 and June 2026. The median arrival is 6 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

Which airline is most reliable on LAS to PDX

The choice of carrier is not cosmetic here. Alaska Airlines arrives on time 83.2% of the time; Southwest Airlines manages 72.3%. Sample sizes sit next to every figure, because a two-point gap across 1,149 flights means less than a ten-point one.

On-time performance by carrier on LAS to PDX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Spirit Airlinesthin sample	128	88.2%	42 min	0.00%	A+
Alaska Airlines	1,534	83.2%	58 min	0.65%	B+
Frontier Airlinesthin sample	173	76.2%	53 min	2.89%	B
Southwest Airlines	1,149	72.3%	56 min	0.26%	C+

Alaska leads Southwest by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Departure window

The best time of day to leave

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 30 points, against 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am518 flights91.3%
8am–11am333 flights85.1%
11am–2pm506 flights85.5%
2pm–5pm586 flights74.5%
5pm–8pm660 flights74.5%
8pm–5am381 flights61.6%

Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 61.6% on time, against 91.3% 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 5pm–8pm window is the busiest, with 660 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 15 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.

Darker means more delays. Figures are on-time percentages.February best, December worst

December is the weak month at 72.4% on time, against 87.4% in February. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 304 flights.

Across the week, Saturday is the strongest day at 83.9% on time and Friday the weakest at 74.6%. 9 points is a smaller lever than departure hour, but it is free.

Delay causes

Why this route gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 56% of the 35,000 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.

Late-arriving aircraft
56%
Carrier
31%
National Airspace System
9%
Extreme weather
3%
Security
0%

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 35,000 reported delay minutes here, that single category outweighs weather by 16 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 35,264 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 91.3% on time here.

Cancellations are rare at 0.60%, 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 actually costs

6.6% 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 are the about an hour kind, which a normal layover absorbs.

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 runs 80.2% on time across 2,983 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 2,984 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 this route

Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 87.4% on time and December 72.4%, a swing of 15 points. If the dates move at all, move them out of December before you think about anything else. 2,964 completed flights over 12 months sit behind that.

Common questions

LAS to PDX questions

How often is LAS to PDX delayed?

About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 21.2% of the 2,984 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on LAS to PDX?

Alaska Airlines leads at 83.2% on time across 1,534 flights. Southwest Airlines is at the other end on 72.3%, a gap of 11 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 LAS to PDX?

The 5am–8am departure window is the strongest at 91.3% on time. The 8pm–5am window is the weakest at 61.6%, 30 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 December delays on LAS to PDX?

December is the weakest month at 72.4% on time, compared with 87.4% in February. Across the year that is 15 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

Direction matters. LAS to PDX and PDX to LAS are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.

Key figures