Carrier route record
F9ONT→LAS
Frontier Airlines · Ontario to Las Vegas
- Flights
- 725
- Period
- July 2025 to June 2026
- Share of route
- 29%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on ONT to LAS lands a B, about a point better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 725 flights, with a median arrival 9 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Frontier on ONT to LAS from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.4%
Arrivals under 15 minutes late, of 716 completed flights
Avg delay
93 min
Across delayed arrivals only, not all flights
Cancelled
1.24%
National rate is 1.81%
Whole route
77.5%
Every carrier on ONT to LAS, 2,479 flights
These figures cover 725 flights between July 2025 and June 2026. Beyond the headline rate, 10.6% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Frontier against every carrier on ONT to LAS
Frontier flew 725 of the 2,479 flights on ONT to LAS, about 29% of it. Its 78.4% on time is about level with the route as a whole at 77.5%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Frontier at 78.4% to Southwest at 77.1%.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Frontier Airlines (this page) | 725 | 78.4% | 93 min | 1.24% | B |
| Southwest Airlines | 1,754 | 77.1% | 53 min | 0.68% | B+ |
Flight by flight
Frontier flight numbers on ONT to LAS
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 29 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am147 flights90.3%
- 8am–11am68 flights91.0%
- 11am–2pm110 flights76.1%
- 2pm–5pm139 flights83.8%
- 5pm–8pm160 flights62.0%
- 8pm–5am101 flights73.3%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 62.0% on time, against 91.0% for the 8am–11am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5pm–8pm window is the busiest, with 160 flights scheduled in it.
Across the year
Frontier on ONT to LAS through the year
Delays peak in April, when the on-time rate falls to 68.3%. February is the strongest month at 87.3%. Moving a flexible trip across that boundary buys 19 points. October was the busiest month here, with 71 flights.
Across the week, Wednesday is the strongest day at 92.4% on time and Friday the weakest at 66.1%. 26 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 14,000 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
- 21%National Airspace System
- 20%Carrier
- 1%Extreme weather
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 14,000 reported delay minutes here, that single category outweighs weather by 52 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 14,476 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 91.0% on time here.
Cancellations sit at 1.24% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.6% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 197 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 82.0% on time across 724 flights, 4 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 4 points of difference.
One caution: this is a thin sample. 725 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 ONT to LAS
Put together: treat all of this as provisional. 725 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 78.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 716 completed flights over 12 months sit behind that.
Related
Where to go next
- ONT to LAS, every carrier
- Frontier on LAS to ONT, the return leg
- Southwest Airlines on ONT to LAS77.1%
- Frontier Airlines network-wide record
- Harry Reid International (LAS) 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.