Carrier route record

ASDEN→PDX

Alaska Airlines · Denver to Portland

Flights: 581
Period: July 2025 to June 2026
Share of route: 14%
Carriers: 5

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

Alaska on DEN to PDX 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 an hour on average. That is a workable record, not a spotless one. That rests on 581 flights. The strongest carrier on the route with a full sample, United Airlines, flew 1,821 at 81.7% on time.

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

On time

77.5%

Arrivals under 15 minutes late, of 577 completed flights

Avg delay

55 min

Across delayed arrivals only, not all flights

Cancelled

0.69%

National rate is 1.81%

Whole route

73.9%

Every carrier on DEN to PDX, 4,289 flights

These figures cover 581 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

Alaska against every carrier on DEN to PDX

Alaska flew 581 of the 4,289 flights on DEN to PDX, about 14% of it. Its 77.5% on time is 4 points better than the route as a whole, which runs 73.9%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from United at 81.7% to SkyWest at 46.2%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. United Airlines arrives on time 81.7% of the time; Southwest Airlines manages 62.5%. Sample sizes sit next to every figure, because a two-point gap across 1,563 flights means less than a ten-point one.

On-time performance by carrier on DEN to PDX
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	1,821	81.7%	60 min	0.44%	B+
Frontier Airlinesthin sample	311	80.3%	69 min	0.64%	B+
Alaska Airlines (this page)	581	77.5%	55 min	0.69%	B+
Southwest Airlines	1,563	62.5%	47 min	0.32%	D+
SkyWest Airlinesthin sample	13	46.2%	42 min	0.00%	F+

The spread between United and Southwest is 19 points, wide enough that it should decide the booking. On a hundred trips that is 19 more arrivals inside the on-time window.

Departure window

When Alaska runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 28 points, against 19 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am20 flights—
8am–11am48 flights91.7%
11am–2pm292 flights85.9%
2pm–5pm—
5pm–8pm221 flights63.3%
8pm–5am—

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

The 5pm–8pm window is where this operation falls apart: 63.3% on time, against 91.7% 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 11am–2pm window is the busiest, with 292 flights scheduled in it.

Across the year

Alaska on DEN to PDX through the year

Darker means more delays. Figures are on-time percentages.April best, July worst

July is the worst month at 56.4% on time, 38 points below April, the best at 94.3%. 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. June was the busiest month here, with 86 flights.

Across the week, Sunday is the strongest day at 82.1% on time and Wednesday the weakest at 70.6%. 12 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Alaska runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 63% of the 7,197 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
63%
Carrier
22%
National Airspace System
14%
Extreme weather
1%

63% 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 7,197 reported delay minutes here, that single category outweighs weather by 45 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 7,197 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 91.7% on time here.

Cancellations are rare at 0.69%, 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

5.5% 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 about an hour, which a normal layover absorbs.

The 991 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 76.8% on time across 582 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 581 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 Alaska on DEN to PDX

Put together: treat all of this as provisional. 581 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 77.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 577 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