Carrier route record
F9LAS→ONT
Frontier Airlines · Las Vegas to Ontario
- Flights
- 724
- 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 LAS to ONT lands a B+, 4 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 724 flights, with a median arrival 13 minutes early.
Set against the rest of the country, Frontier's LAS to ONT record is 4 points better than the US average of 77.6%. That gap is worth roughly 44 fewer late arrivals for every thousand flights.
Key figures
On time
82.0%
Arrivals under 15 minutes late, of 718 completed flights
Avg delay
77 min
Across delayed arrivals only, not all flights
Cancelled
0.83%
National rate is 1.81%
Whole route
75.8%
Every carrier on LAS to ONT, 2,479 flights
These figures cover 724 flights between July 2025 and June 2026. The median arrival is 13 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 LAS to ONT
Frontier flew 724 of the 2,479 flights on LAS to ONT, about 29% of it. Its 82.0% on time is 6 points better than the route as a whole, which runs 75.8%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Frontier at 82.0% to Southwest at 73.2%.
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) | 724 | 82.0% | 77 min | 0.83% | B+ |
| Southwest Airlines | 1,755 | 73.2% | 49 min | 0.74% | C+ |
Flight by flight
Frontier flight numbers on LAS to ONT
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 21 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–8am98 flights92.9%
- 8am–11am79 flights88.5%
- 11am–2pm119 flights86.6%
- 2pm–5pm135 flights74.6%
- 5pm–8pm169 flights82.7%
- 8pm–5am124 flights71.9%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 92.9% of the time, against 71.9% for the overnight window. That is 21 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 169 flights scheduled in it.
Across the year
Frontier on LAS to ONT through the year
December is the weak month at 73.1% on time, against 86.8% in September. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. October was the busiest month here, with 71 flights.
Across the week, Saturday is the strongest day at 86.7% on time and Monday the weakest at 75.0%. 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 55% of the 9,881 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.
- 55%Late-arriving aircraft
- 35%Carrier
- 7%National Airspace System
- 2%Extreme weather
55% 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 9,881 reported delay minutes here, that single category outweighs weather by 26 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 9,881 reported delay minutes.
The largest share of delay minutes, 35%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 3,491 of the 9,881 delay minutes reported here.
Cancellations are rare at 0.83%, 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
7.0% 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.
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 5am–8am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 78.4% on time across 725 flights, 4 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 4 points of difference.
One caution: this is a thin sample. 724 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 LAS to ONT
Put together: treat all of this as provisional. 724 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 82.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 718 completed flights over 12 months sit behind that.
Related
Where to go next
- LAS to ONT, every carrier
- Frontier on ONT to LAS, the return leg
- Southwest Airlines on LAS to ONT73.2%
- 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.