Carrier route record

UASLC→LAX

United Airlines · Salt Lake City to Los Angeles

Flights: 148
Period: July 2025 to June 2026
Share of route: 4%
Carriers: 6

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

United on SLC to LAX earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 14 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 35 minutes. That rests on 148 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 691 at 89.6% on time.

Set against the rest of the country, United's SLC to LAX record is 14 points better than the US average of 77.6%. That gap is worth roughly 143 fewer late arrivals for every thousand flights.

On time

91.9%

Arrivals under 15 minutes late, of 148 completed flights

Avg delay

34 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

Whole route

86.2%

Every carrier on SLC to LAX, 4,146 flights

These figures cover 148 flights between July 2025 and June 2026. The median arrival is 9 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 SLC to LAX

United flew 148 of the 4,146 flights on SLC to LAX, about 4% of it. Its 91.9% on time is 6 points better than the route as a whole, which runs 86.2%. Ranked by on-time rate it is first of six carriers on the route, where the range runs from United at 91.9% to Southwest at 80.4%. One 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 89.6% of the time; Southwest Airlines manages 80.4%. Sample sizes sit next to every figure, because a two-point gap across 374 flights means less than a ten-point one.

On-time performance by carrier on SLC to LAX
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines (this page)thin sample	148	91.9%	34 min	0.00%	A+
Spirit Airlinesthin sample	23	90.9%	29 min	4.35%	A−
SkyWest Airlines	691	89.6%	78 min	0.00%	A+
Frontier Airlines	456	88.4%	74 min	1.54%	A
Delta Air Lines	2,454	85.4%	51 min	0.41%	A+
Southwest Airlines	374	80.4%	46 min	0.27%	B+

SkyWest leads Southwest by 9 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Departure window

When United 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 148 flights.

5am–8am49 flights89.8%
8am–11am94 flights92.6%
11am–2pm5 flights—
2pm–5pm—
5pm–8pm—
8pm–5am—

Scale runs 80% to 100%. Rows with fewer than 30 flights show a dash.

The 8am–11am window is the strongest at 92.6% on time. The full set of windows spans 3 points.

Across the year

United on SLC to LAX through the year

Oct–Dec 202513 flights—
Jan–Mar 202685 flights89.4%
Apr–Jun 202650 flights96.0%

Scale runs 80% 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 91.9% on time across 148 flights.

Split by quarter, United on SLC to LAX logged 13 flights in Oct–Dec 2025, 85 flights in Jan–Mar 2026 and 50 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 91.9% annual figure is the one to use.

Delay causes

Why United runs late on this route

One category carries most of the weight here. Carrier accounts for 61% of the 410 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.

Carrier
61%
National Airspace System
39%

The largest share of delay minutes, 61%, 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 250 of the 410 delay minutes reported here. The split is drawn from 410 reported delay minutes.

39% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 160 minutes out of 410, against a national NAS share of 21%.

Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 1.4% 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 590 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 is a different operation and performs like one: it runs 88.6% on time across 149 flights, 3 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 3 points of difference.

One caution: this is a thin sample. 148 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 SLC to LAX

Put together: treat all of this as provisional. 148 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 91.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 148 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