HOU to ONT flight delays
Houston, TX (HOU) Ontario, CA (ONT) · 1,345 miles
362 flights · January 2025 – August 2026 · US Bureau of Transportation Statistics
80.78%
Arrived on time
Within 15 minutes of schedule
0.28%
Cancelled
Share of scheduled flights
60 min
When late, late by
Average across delayed arrivals
13 min
Delay per flight
Averaged over every flight flown
What the record says about this route
The season swings this route hard. In July it ran 40.1 points more punctual than in June — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.
The two directions do not behave alike. ONT to HOU arrives on time 15.6 points less often than the outbound. Delay accumulates through the flying day, so whichever direction is scheduled later tends to carry the worse record — which is an argument for booking the morning departure if the choice exists.
This route does better than its own airport. Departures from HOU overall run 7 points less punctual than this particular one — so whatever congestion HOU has, this route is largely escaping it.
Only Southwest Airlines flies this route in the published record, so there is no choice to weigh — the route's figures and the airline's are the same figures.
Which airline should you fly on this route?
Over January 2025 – August 2026, Southwest Airlines arrived on time most often on HOU to ONT. Flights ran closest to schedule in July and worst in June.
Every airline on HOU to ONT
Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.
| Airline | Flights | On time | Cancelled | Avg delay | Grade |
|---|---|---|---|---|---|
| Southwest Airlines | 362 | 80.78% | 0.28% | 60 min | B |
Month by month
Share of flights that arrived within 15 minutes of schedule, by month flown.
The return leg
ONT to HOU Ontario back to Houston 65.19% on time DOther routes from Houston
Common questions
Are flights from Houston to Ontario usually delayed?
80.78% of flights on the HOU to ONT route arrived within 15 minutes of schedule, so roughly 2 in every ten arrived late. That is better than the average route in this record.
Which airlines fly from Houston to Ontario?
Only Southwest Airlines appears in the published record on this route, with 362 flights and 80.78% arriving on time.
How often are HOU to ONT flights cancelled?
0.28% of scheduled flights did not operate — about 3 in every thousand. That is in the normal range.
What is the best month to fly Houston to Ontario?
July, when 96.8% of flights arrived on time. The worst was June at 56.7%.
When HOU to ONT flights are late, how late are they?
About 60 minutes on average across the flights that arrived more than 15 minutes behind schedule.
What these figures do and do not tell you
Everything on this page is counted from the flights that actually operated on HOU to ONT during January 2025 – August 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.
A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.
Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →