Carrier route record
F9SLC→LAX
Frontier Airlines · Salt Lake City to Los Angeles
- Flights
- 456
- Period
- July 2025 to June 2026
- Share of route
- 11%
- Carriers
- 6
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier 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 11 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 456 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 691 at 89.6% on time.
SkyWest Airlines is the most reliable of the three carriers covered here at 89.6% on time across 691 flights.
Key figures
On time
88.4%
Arrivals under 15 minutes late, of 449 completed flights
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
1.54%
National rate is 1.81%
Whole route
86.2%
Every carrier on SLC to LAX, 4,146 flights
These figures cover 456 flights between July 2025 and June 2026. The median arrival is 17 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 SLC to LAX
Frontier flew 456 of the 4,146 flights on SLC to LAX, about 11% of it. Its 88.4% on time is 2 points better than the route as a whole, which runs 86.2%. Ranked by on-time rate it is number four of six carriers on the route, where the range runs from United at 91.9% to Southwest at 80.4%. 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 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlinesthin 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 (this page) | 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.
Flight by flight
Frontier flight numbers on SLC to LAX
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 17 points, against 9 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am211 flights92.9%
- 11am–2pm86 flights75.6%
- 2pm–5pm119 flights88.8%
- 5pm–8pm40 flights91.7%
- 8pm–5am—
Scale runs 65% to 100%. 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 75.6% on time against 92.9% 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 8am–11am window is the busiest, with 211 flights scheduled in it.
Across the year
Frontier on SLC to LAX through the year
May is the best month on the calendar at 100.0% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. March was the busiest month here, with 60 flights.
Across the week, Tuesday is the strongest day at 95.1% on time and Thursday the weakest at 82.9%. 12 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 59% of the 3,847 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.
- 59%Late-arriving aircraft
- 29%Carrier
- 12%National Airspace System
59% 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 3,847 reported delay minutes here, that single category outweighs weather by 59 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 3,847 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 92.9% on time here.
Cancellations sit at 1.54% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 4.2% 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 85.2% on time across 456 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. 456 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 SLC to LAX
Put together: treat all of this as provisional. 456 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 88.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 449 completed flights over 12 months sit behind that.
Related
Where to go next
- SLC to LAX, every carrier
- Frontier on LAX to SLC, the return leg
- United Airlines on SLC to LAX91.9%
- SkyWest Airlines on SLC to LAX89.6%
- Delta Air Lines on SLC to LAX85.4%
- Southwest Airlines on SLC to LAX80.4%
- Frontier Airlines network-wide record
- Salt Lake City International (SLC) delay statistics
- Los Angeles International (LAX) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.