Carrier route record
F9LAX→SLC
Frontier Airlines · Los Angeles to Salt Lake City
- 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 LAX to SLC 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 8 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
85.2%
Arrivals under 15 minutes late, of 452 completed flights
Avg delay
76 min
Across delayed arrivals only, not all flights
Cancelled
0.88%
National rate is 1.81%
Whole route
87.7%
Every carrier on LAX to SLC, 4,144 flights
These figures cover 456 flights between July 2025 and June 2026. The median arrival is 10 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 LAX to SLC
Frontier flew 456 of the 4,144 flights on LAX to SLC, about 11% of it. Its 85.2% on time is 3 points worse than the route as a whole, which runs 87.7%. Ranked by on-time rate it is number five of six carriers on the route, where the range runs from Spirit at 90.9% to Southwest at 81.7%. 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 89.6% of the time; Southwest Airlines manages 81.7%. 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 |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 23 | 90.9% | 29 min | 4.35% | A− |
| SkyWest Airlines | 691 | 89.6% | 87 min | 0.00% | A+ |
| United Airlinesthin sample | 149 | 88.6% | 65 min | 0.00% | A+ |
| Delta Air Lines | 2,451 | 88.5% | 79 min | 0.41% | A+ |
| Frontier Airlines (this page) | 456 | 85.2% | 76 min | 0.88% | A+ |
| Southwest Airlines | 374 | 81.7% | 46 min | 0.53% | B+ |
SkyWest leads Southwest by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Departure window
When Frontier 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 456 flights.
- 5am–8am—
- 8am–11am121 flights88.4%
- 11am–2pm146 flights84.2%
- 2pm–5pm62 flights83.9%
- 5pm–8pm127 flights83.7%
- 8pm–5am—
Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.
The early departures do better, though not dramatically: 88.4% on time for the 8am–11am window against 83.7% for 5pm–8pm. Worth taking if the schedule allows, not worth an extra connection. The 11am–2pm window is the busiest, with 146 flights scheduled in it.
Across the year
Frontier on LAX to SLC through the year
November is the best month on the calendar at 92.7% 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 Friday the weakest at 77.5%. 18 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 56% of the 5,057 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.
- 56%Late-arriving aircraft
- 32%Carrier
- 12%National Airspace System
- 0%Extreme weather
56% 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 5,057 reported delay minutes here, that single category outweighs weather by 56 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 5,057 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 88.4% on time here.
Cancellations are rare at 0.88%, 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
5.1% 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.
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 88.4% on time across 456 flights, 3 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 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 LAX to SLC
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 85.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 452 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to SLC, every carrier
- Frontier on SLC to LAX, the return leg
- SkyWest Airlines on LAX to SLC89.6%
- United Airlines on LAX to SLC88.6%
- Delta Air Lines on LAX to SLC88.5%
- Southwest Airlines on LAX to SLC81.7%
- Frontier Airlines network-wide record
- Los Angeles International (LAX) delay statistics
- Salt Lake City International (SLC) delay statistics
- Why the first flight of the morning is statistically safest
- Worst months to fly in the US, ranked by the data
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.