Carrier route record

F9LAX→PDX

Frontier Airlines · Los Angeles to Portland

Flights: 218
Period: July 2025 to June 2026
Share of route: 5%
Carriers: 4

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

Frontier on LAX to PDX earns an A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 50 minutes. That rests on 218 flights. The strongest carrier on the route with a full sample, Alaska Airlines, flew 1,899 at 90.0% on time.

Alaska Airlines is the most reliable of the three carriers covered here at 90.0% on time across 1,899 flights.

On time

85.1%

Arrivals under 15 minutes late, of 215 completed flights

Avg delay

49 min

Across delayed arrivals only, not all flights

Cancelled

1.38%

National rate is 1.81%

Whole route

86.4%

Every carrier on LAX to PDX, 4,406 flights

These figures cover 218 flights between July 2025 and June 2026. The median arrival is 13 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

Frontier against every carrier on LAX to PDX

Frontier flew 218 of the 4,406 flights on LAX to PDX, about 5% of it. Its 85.1% on time is about level with the route as a whole at 86.4%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Alaska at 90.0% to SkyWest at 76.2%.

The choice of carrier is not cosmetic here. Alaska Airlines arrives on time 90.0% of the time; SkyWest Airlines manages 76.2%. Sample sizes sit next to every figure, because a two-point gap across 599 flights means less than a ten-point one.

On-time performance by carrier on LAX to PDX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Alaska Airlines	1,899	90.0%	51 min	0.90%	A+
Delta Air Lines	1,690	86.2%	74 min	0.89%	A+
Frontier Airlines (this page)thin sample	218	85.1%	49 min	1.38%	A
SkyWest Airlines	599	76.2%	87 min	0.33%	B+

The spread between Alaska and SkyWest is 14 points, wide enough that it should decide the booking. On a hundred trips that is 14 more arrivals inside the on-time window.

Departure window

When Frontier runs best on this route

Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 218 flights.

There are not enough flights in each departure window to split Frontier's LAX to PDX record by time of day without the percentages moving on noise. The headline rate of 85.1% is the reliable figure here.

Across the year

Frontier on LAX to PDX through the year

Jul–Sep 202565 flights76.2%
Oct–Dec 202558 flights86.2%
Jan–Mar 202641 flights82.5%
Apr–Jun 202654 flights96.3%

Scale runs 70% to 100%. 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 85.1% on time across 218 flights.

Frontier on LAX to PDX did not run the same all year. Its best quarter was Apr–Jun 2026 at 96.3% on time and its weakest Jul–Sep 2025 at 76.2%, a swing of 20 points on roughly 55 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Monday is the strongest day at 91.5% on time and Friday the weakest at 77.8%. 14 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Frontier runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 66% of the 1,555 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
29%
National Airspace System
5%

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 1,555 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 1,555 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 85.8% on time here.

Cancellations sit at 1.38% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 4.2% 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 833 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 84.9% on time across 218 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. 218 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 Frontier on LAX to PDX

Put together: treat all of this as provisional. 218 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 85.1% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 215 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