Carrier route record

F9PDX→LAX

Frontier Airlines · Portland to Los Angeles

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 PDX to LAX earns a B. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 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, Delta Air Lines, flew 1,689 at 90.9% on time.

Delta Air Lines is the most reliable of the three carriers covered here at 90.9% on time across 1,689 flights.

On time

84.9%

Arrivals under 15 minutes late, of 212 completed flights

Avg delay

52 min

Across delayed arrivals only, not all flights

Cancelled

2.75%

National rate is 1.81%

Whole route

87.4%

Every carrier on PDX to LAX, 4,403 flights

These figures cover 218 flights between July 2025 and June 2026. The median arrival is 11 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 PDX to LAX

Frontier flew 218 of the 4,403 flights on PDX to LAX, about 5% of it. Its 84.9% on time is 3 points worse than the route as a whole, which runs 87.4%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Delta at 90.9% to SkyWest at 81.0%.

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 90.9% of the time; SkyWest Airlines manages 81.0%. 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 PDX to LAX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	1,689	90.9%	108 min	0.89%	A+
Alaska Airlines	1,897	86.5%	49 min	0.84%	A+
Frontier Airlines (this page)thin sample	218	84.9%	52 min	2.75%	B
SkyWest Airlines	599	81.0%	117 min	0.33%	B+

Delta leads SkyWest by 10 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Departure window

When Frontier runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 13 points, against 10 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am36 flights91.7%
11am–2pm95 flights79.1%
2pm–5pm22 flights—
5pm–8pm65 flights89.1%
8pm–5am—

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

The weak window here is the middle of the day, not the evening: 11am–2pm runs 79.1% on time against 91.7% for 8am–11am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 11am–2pm window is the busiest, with 95 flights scheduled in it.

Across the year

Frontier on PDX to LAX through the year

Jul–Sep 202565 flights73.8%
Oct–Dec 202558 flights87.7%
Jan–Mar 202641 flights90.0%
Apr–Jun 202654 flights90.7%

Scale runs 65% to 95%. 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 84.9% on time across 218 flights.

Frontier on PDX to LAX did not run the same all year. Its best quarter was Apr–Jun 2026 at 90.7% on time and its weakest Jul–Sep 2025 at 73.8%, a swing of 17 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, Saturday is the strongest day at 90.9% on time and Thursday the weakest at 80.5%. 10 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 57% of the 1,672 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
57%
Carrier
32%
National Airspace System
10%

57% 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 1,672 reported delay minutes here, that single category outweighs weather by 57 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 1,672 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 run at 2.75%, against 1.81% nationally. That is roughly one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and stage length

What a delay here costs

5.2% 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 50 minutes, which a normal layover absorbs.

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 85.1% 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 PDX to LAX

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 84.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 212 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