Carrier route record
DLLAX→SLC
Delta Air Lines · Los Angeles to Salt Lake City
- Flights
- 2,457
- 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 LAX to SLC 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 11 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 2,457 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 720 at 88.0% on time.
Set against the rest of the country, Delta's LAX to SLC record is 11 points better than the US average of 77.3%. That gap is worth roughly 111 fewer late arrivals for every thousand flights.
Key figures
On time
88.4%
Arrivals under 15 minutes late, of 2,438 completed flights
Avg delay
80 min
Across delayed arrivals only, not all flights
Cancelled
0.53%
National rate is 1.89%
Whole route
87.2%
Every carrier on LAX to SLC, 4,195 flights
These figures cover 2,457 flights between September 2025 and August 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.
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Carrier by carrier
Delta against every carrier on LAX to SLC
Delta flew 2,457 of the 4,195 flights on LAX to SLC, most of the route. Its 88.4% on time is about level with the route as a whole at 87.2%. Ranked by on-time rate it is number three of six carriers on the route, where the range runs from Spirit at 90.9% to Southwest at 79.7%. 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 88.0% of the time; Southwest Airlines manages 79.7%. Sample sizes sit next to every figure, because a two-point gap across 371 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 23 | 90.9% | 29 min | 4.35% | A− |
| United Airlinesthin sample | 149 | 88.6% | 65 min | 0.00% | A+ |
| Delta Air Lines (this page) | 2,457 | 88.4% | 80 min | 0.53% | A+ |
| SkyWest Airlines | 720 | 88.0% | 69 min | 0.00% | A+ |
| Frontier Airlines | 475 | 85.3% | 75 min | 1.26% | A |
| Southwest Airlines | 371 | 79.7% | 47 min | 0.27% | B+ |
SkyWest leads Southwest by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Delta flight numbers on LAX to SLC
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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 11 points, against 8 points between the best and worst carrier.
- 5am–8am713 flights93.4%
- 8am–11am365 flights92.0%
- 11am–2pm731 flights86.9%
- 2pm–5pm—
- 5pm–8pm648 flights82.4%
- 8pm–5am—
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 93.4% of the time, against 82.4% 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 11am–2pm window is the busiest, with 731 flights scheduled in it.
Across the year
Delta on LAX to SLC through the year
August is the worst month at 82.3% on time, 12 points below October, the best at 94.2%. 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, Tuesday is the strongest day at 90.4% on time and Sunday the weakest at 84.7%, a spread of 6 points.
Arrival by arrival
How late Delta on LAX to SLC runs when it is late
Delta on LAX to SLC often beats the schedule: 853 of 2,438 completed flights, 35%, arrived 15 minutes or more early. The 284 late arrivals split 90 under half an hour, 82 between 30 and 60 minutes, and 112 an hour or more.
- 15+ min early853 flights35.0%
- Within 15 min1,301 flights53.4%
- 15–29 min late90 flights3.7%
- 30–59 min late82 flights3.4%
- 1–2 hours late58 flights2.4%
- 2+ hours late54 flights2.2%
Scale runs 0% to 100%.
Share of 2,438 completed flights by arrival against schedule.
81 of 337 late departures made up the time and arrived on time, 24% of them. Only 28 left on time and still arrived late.
The worst days
Worst days for Delta on LAX to SLC
The latest arrival of the period was on 5 December 2025, 14 hours 13 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on five of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 5 December 2025 | 14 hours 13 minutes | Carrier |
| 30 April 2026 | 12 hours 13 minutes | Carrier |
| 3 November 2025 | 10 hours 41 minutes | Carrier |
| 26 June 2026 | 9 hours 54 minutes | Carrier |
| 28 January 2026 | 8 hours 47 minutes | Carrier |
Delay causes
Why Delta runs late on this route
Carrier accounts for 68% of the 23,000 delay minutes carriers reported here, and the remaining four split what is left.
- 68%Carrier
- 27%Late-arriving aircraft
- 5%National Airspace System
- 0%Security
- 0%Extreme weather
The largest share of delay minutes, 68%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 15,000 of the 23,000 delay minutes reported here. The split is drawn from 22,638 reported delay minutes.
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 4.6% 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 83.5% on time across 2,459 flights, 5 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 5 points of difference.
The sample behind these figures is 2,457 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 LAX to SLC
Put together: avoid the 5pm–8pm departure. It runs 82.4% on time against 93.4% for the 5am–8am slot, and that 11 points is the largest single thing you control here. SkyWest Airlines is the strongest operator if the fares are close. 2,438 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to SLC, every carrier
- Delta on SLC to LAX, the return leg
- United Airlines on LAX to SLC88.6%
- SkyWest Airlines on LAX to SLC88.0%
- Frontier Airlines on LAX to SLC85.3%
- Southwest Airlines on LAX to SLC79.7%
- Delta Air Lines network-wide record
- Los Angeles International (LAX) delay statistics
- Salt Lake City International (SLC) delay statistics
- The best time of day to fly, according to 7.05 million flight records
- Worst months to fly in the US, ranked by the data
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.