AUS to ONT flight delays & on-time performance
Nonstop flights from Austin Bergstrom International Airport to Ontario International Airport · 1,196 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at AUS or ONT right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Austin (AUS) to Ontario (ONT) arrived on time 74% of the time in Aug 2025 – Jul 2026, worse than the 78% national average.
- 0.6% were cancelled, and 6% arrived an hour or more late.
- Southwest Airlines is the only airline reporting nonstop flights on this route.
- Departures scheduled around 11am did best (94% on time); around 8pm did worst (64%).
- Tuesday was the most reliable day to fly (88% on time) and Sunday the least (53%).
- The largest source of delay minutes was late-arriving aircraft (56%).
Which airline is most on time from AUS to ONT?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Southwest Airlines | 74% | 0.6% | 13 min | 6.0% | 335 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 11am94%18 flights
- 1pm89%90 flights
- 2pm70%63 flights
- 3pm85%13 flights
- 4pm67%81 flights
- 7pm66%29 flights
- 8pm64%34 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday84%3.8% cancelled
- Tuesday88%0.0% cancelled
- Wednesday79%0.0% cancelled
- Thursday77%0.0% cancelled
- Friday68%0.0% cancelled
- Saturday70%0.0% cancelled
- Sunday53%0.0% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft56%
- Airline (crew, maintenance, cleaning, fueling)32%
- Air traffic control & airport congestion11%
- Extreme weather1%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)50%
- Air traffic control & airport congestion50%
- Extreme weather0%
- Security0%
AUS to ONT: common questions
- How often are AUS to ONT flights on time?
- 74% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Austin to Ontario cancelled?
- 0.6% of scheduled flights were cancelled (2 of 335).
- How long are typical delays?
- Across all flights the average arrival delay was 13 min (early arrivals count as zero). Flights that were late arrived 47 min behind schedule on average, and 6.0% of flights were an hour or more late.
- How long is taxi time at AUS?
- Flights on this route spent 13 min taxiing from the gate to takeoff on average.
Related routes
Return trip: ONT to AUS — 74% on time
More flights from Austin
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: AUS → ONT, nonstop flights by US airlines that report to the DOT. How we calculate this.