Carrier route record

UALAX→PHX

United Airlines · Los Angeles to Phoenix

Flights: 339
Period: July 2025 to June 2026
Share of route: 4%
Carriers: 7

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

United on LAX to PHX 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 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 339 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 2,590 at 87.2% on time.

SkyWest Airlines is the most reliable of the four carriers covered here at 87.2% on time across 2,590 flights.

On time

86.6%

Arrivals under 15 minutes late, of 337 completed flights

Avg delay

74 min

Across delayed arrivals only, not all flights

Cancelled

0.59%

National rate is 1.81%

Whole route

80.9%

Every carrier on LAX to PHX, 7,608 flights

These figures cover 339 flights between July 2025 and June 2026. The median arrival is 8 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

United against every carrier on LAX to PHX

United flew 339 of the 7,608 flights on LAX to PHX, about 4% of it. Its 86.6% on time is 6 points better than the route as a whole, which runs 80.9%. Ranked by on-time rate it is number two of seven carriers on the route, where the range runs from SkyWest at 87.2% to Frontier at 74.6%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 87.2% of the time; Frontier Airlines manages 74.6%. Sample sizes sit next to every figure, because a two-point gap across 488 flights means less than a ten-point one.

On-time performance by carrier on LAX to PHX
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	2,590	87.2%	59 min	0.73%	A+
United Airlines (this page)thin sample	339	86.6%	74 min	0.59%	A+
Envoy Airthin sample	6	83.3%	22 min	0.00%	B+
Delta Air Linesthin sample	142	83.0%	77 min	0.70%	B+
American Airlines	2,026	79.1%	91 min	0.49%	B+
Southwest Airlines	2,017	74.9%	51 min	1.09%	C
Frontier Airlines	488	74.6%	72 min	1.43%	C

The spread between SkyWest and Frontier is 13 points, wide enough that it should decide the booking. On a hundred trips that is 13 more arrivals inside the on-time window.

Departure window

When United runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 11 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am60 flights89.8%
11am–2pm77 flights89.6%
2pm–5pm65 flights89.2%
5pm–8pm82 flights79.0%
8pm–5am55 flights87.3%

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

Book the morning departure. Flights leaving between 8am–11am arrive on time 89.8% of the time, against 79.0% for the evening window. That is 11 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 82 flights scheduled in it.

Across the year

United on LAX to PHX through the year

Jul–Sep 2025142 flights83.0%
Oct–Dec 202577 flights83.1%
Jan–Mar 202673 flights91.7%
Apr–Jun 202647 flights95.7%

Scale runs 75% 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 86.6% on time across 339 flights.

United on LAX to PHX did not run the same all year. Its best quarter was Apr–Jun 2026 at 95.7% on time and its weakest Jul–Sep 2025 at 83.0%, a swing of 13 points on roughly 85 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, Tuesday is the strongest day at 94.1% on time and Wednesday the weakest at 78.3%. 16 points is a smaller lever than departure hour, but it is free.

Delay causes

Why United runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 47% of the 3,326 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
47%
Carrier
38%
National Airspace System
12%
Extreme weather
3%

47% 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 3,326 reported delay minutes here, that single category outweighs weather by 14 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 3,326 reported delay minutes.

The largest share of delay minutes, 38%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 1,270 of the 3,326 delay minutes reported here.

Cancellations are rare at 0.59%, 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

5.0% 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 a little over an hour, which a normal layover absorbs.

At 370 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.

The return leg runs 87.8% on time across 339 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.

One caution: this is a thin sample. 339 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 United on LAX to PHX

Put together: treat all of this as provisional. 339 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 86.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 337 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