ONT to LAS flight delays

ONT LAS Ontario to Harry Reid · 197 miles

7,978 flights were scheduled from ONT to LAS over July 2023 through June 2026. Of the 7,903 that made the trip, 78.1% reached the gate less than 15 minutes behind schedule. These are arrival figures: “on time” means the flight reached the gate less than 15 minutes behind schedule. Arrivals are what decide whether you make the connection, so route and airline pages are scored on them rather than on pushback.

Data through June 2026 · Bureau of Transportation Statistics

The route in brief

Flights in the window
7,978
Arrived on time
78.1%
Cancelled
0.9%
Scheduled distance
197 miles

Cancellations are counted against everything scheduled. Diverted flights are counted with them rather than as very late arrivals, which is why the on-time share and the cancellation rate do not add up to everything that happened.

Airline by airline

Airlines with at least 100 flights on ONT–LAS, busiest first. Same route, same weather, same air traffic — which makes this the fairest comparison on the site.

Airline Arrived on time Typical delay Cancelled Flights
Southwest Airlines 79% 53 min 0.6% 5,478
Frontier Airlines 76.1% 97 min 1.5% 2,500

Month by month

May was the month to avoid on ONT–LAS: 72% of flights arrived on time, against 86.7% in December. Each bar pools three years of that calendar month.

Share of flights that arrived on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 78.1%.
Arrival on-time share, ONT to LAS, by calendar month
Month Share flights that arrived on time Flights
January 82.4% 631
February 85.1% 568
March 74.3% 653
April 73.3% 657
May 72% 662
June 72.5% 656
July 75.9% 682
August 75.6% 679
September 77.4% 688
October 79.2% 762
November 83.7% 690
December 86.7% 650

Both ends of the route

A route’s record is built out of two airports’ habits. The hour-by-hour grid for each is on its own page.

ONT to LAS in one number

ONT → LAS

When a flight on this route was late, it was late by about 68 min.

July 2023–June 2026 · 7,978 flights

78.1% of flights arrived on time

Questions about ONT to LAS

Which airline is most reliable from ONT to LAS?
Southwest Airlines — its flights on this pairing arrived on time 79% of the time, with 5,478 scheduled. Frontier Airlines came in at 76.1% over 2,500 scheduled. Airlines with fewer than 100 flights on the route are not rated.
What is the worst month to fly ONT to LAS?
May, at 72% of arrivals on time, with 662 flights scheduled. December was the best of the year at 86.7%.
How late are ONT–LAS flights when they are late?
68 min on average, counting only the flights that arrived 15 minutes or more behind schedule. The on-time flights are left out of that average on purpose — mixing them in would flatter it.
How often is the ONT to LAS flight cancelled?
0.9% of scheduled flights on this route were cancelled, July 2023 through June 2026. Diverted flights are counted with the cancellations rather than as late arrivals.
Are these departure or arrival numbers?
Arrival. A flight counts as on time here if it reached the gate at LAS less than 15 minutes behind schedule. Airport pages score departures instead, because that is the number you can act on when you pick a booking time.