Carrier route record

DLSLC→LAX

Delta Air Lines · Salt Lake City to Los Angeles

Flights: 2,459
Period: September 2025 to August 2026
Share of route: 59%
Carriers: 6

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Delta Air Lines.

Delta on SLC to LAX lands a B+, 6 points better than the national rate of 77.3%. About one flight in six arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That rests on 2,459 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 720 at 91.1% on time.

SkyWest Airlines is the most reliable of the three carriers covered here at 91.1% on time across 720 flights.

On time

83.5%

Arrivals under 15 minutes late, of 2,446 completed flights

Avg delay

52 min

Across delayed arrivals only, not all flights

Cancelled

0.53%

National rate is 1.89%

Whole route

85.6%

Every carrier on SLC to LAX, 4,196 flights

These figures cover 2,459 flights between September 2025 and August 2026. The median arrival is 7 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.

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Carrier by carrier

Delta against every carrier on SLC to LAX

Delta flew 2,459 of the 4,196 flights on SLC to LAX, most of the route. Its 83.5% on time is 2 points worse than the route as a whole, which runs 85.6%. Ranked by on-time rate it is number five of six carriers on the route, where the range runs from United at 91.9% to Southwest at 80.3%. 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 91.1% of the time; Southwest Airlines manages 80.3%. Sample sizes sit next to every figure, because a two-point gap across 371 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 Airlinesthin sample	148	91.9%	34 min	0.00%	A+
SkyWest Airlines	720	91.1%	77 min	0.00%	A+
Spirit Airlinesthin sample	23	90.9%	29 min	4.35%	A−
Frontier Airlines	475	90.0%	73 min	1.05%	A
Delta Air Lines (this page)	2,459	83.5%	52 min	0.53%	B+
Southwest Airlines	371	80.3%	44 min	0.27%	B+

SkyWest leads Southwest by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Flight by flight

Delta flight numbers on SLC to LAX

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Departure window

When Delta runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 14 points, against 11 points between the best and worst carrier.

5am–8am310 flights91.5%
8am–11am412 flights90.8%
11am–2pm365 flights86.5%
2pm–5pm370 flights78.1%
5pm–8pm365 flights81.5%
8pm–5am637 flights77.5%

Scale runs 70% to 95%.

Book the early departure. Flights leaving between 5am–8am arrive on time 91.5% of the time, against 77.5% for the overnight window. That is 14 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8pm–5am window is the busiest, with 637 flights scheduled in it.

Across the year

Delta on SLC to LAX through the year

Darker means more delays. Figures are on-time percentages.November best, August worst

August is the worst month at 72.2% on time, 17 points below November, the best at 88.7%. 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. March was the busiest month here, with 213 flights.

Across the week, Wednesday is the strongest day at 88.4% on time and Sunday the weakest at 78.1%, a spread of 10 points.

Arrival by arrival

How late Delta on SLC to LAX runs when it is late

Delta on SLC to LAX often beats the schedule: 716 of 2,446 completed flights, 29%, arrived 15 minutes or more early. The 403 late arrivals split 182 under half an hour, 127 between 30 and 60 minutes, and 94 an hour or more.

15+ min early716 flights29.3%
Within 15 min1,327 flights54.3%
15–29 min late182 flights7.4%
30–59 min late127 flights5.2%
1–2 hours late58 flights2.4%
2+ hours late36 flights1.5%

Scale runs 0% to 100%.

Share of 2,446 completed flights by arrival against schedule.

106 of 418 late departures made up the time and arrived on time, 25% of them. 91 flights left on time and still arrived late.

The worst days

Worst days for Delta on SLC to LAX

The latest arrival of the period was on 6 August 2026, 14 hours 37 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on four of the five worst days.

The latest arrivals of Delta on SLC to LAX in the period
Date	Arrived late by	Largest filed cause
6 August 2026	14 hours 37 minutes	Carrier
18 February 2026	13 hours 53 minutes	Carrier
18 April 2026	4 hours 37 minutes	Carrier
17 July 2026	4 hours 16 minutes	Carrier
18 February 2026	4 hours 8 minutes	Extreme weather

Delay causes

Why Delta runs late on this route

Carrier accounts for 52% of the 21,000 delay minutes carriers reported here, and the remaining four split what is left.

Carrier
52%
Late-arriving aircraft
30%
National Airspace System
14%
Extreme weather
4%

The largest share of delay minutes, 52%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 11,000 of the 21,000 delay minutes reported here. The split is drawn from 20,926 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 91.5% on time here.

Cancellations are rare at 0.53%, below the national 1.89% 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

Badly late arrivals are rare here: only 3.8% land an hour or more behind schedule, against 8.3% 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.

The return leg is a different operation and performs like one: it runs 88.4% on time across 2,457 flights, 5 points above 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 5 points of difference.

The sample behind these figures is 2,459 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.

What to do with this

Booking Delta on SLC to LAX

Put together: the calendar is the biggest lever here, not the carrier or the hour. November runs 88.7% on time and August 72.2%, a swing of 17 points. If the dates move at all, move them out of August before you think about anything else. 2,446 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures