ONT to SMF flight delays & on-time performance
Nonstop flights from Ontario International Airport to Sacramento International Airport · 390 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at ONT or SMF right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Ontario (ONT) to Sacramento (SMF) arrived on time 86% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.3% were cancelled, and 4% arrived an hour or more late.
- Southwest Airlines is the only airline reporting nonstop flights on this route.
- Departures scheduled around 8am did best (98% on time); around 3pm did worst (65%).
- Wednesday was the most reliable day to fly (89% on time) and Sunday the least (80%).
- The largest source of delay minutes was late-arriving aircraft (73%).
Which airline is most on time from ONT to SMF?
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 | 86% | 0.3% | 8 min | 4.1% | 2,114 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am98%43 flights
- 6am98%230 flights
- 7am96%98 flights
- 8am98%148 flights
- 9am95%128 flights
- 10am95%94 flights
- 11am84%123 flights
- 12pm87%168 flights
- 1pm74%139 flights
- 2pm92%59 flights
- 3pm65%114 flights
- 4pm84%103 flights
- 5pm87%147 flights
- 6pm73%183 flights
- 7pm82%129 flights
- 8pm76%190 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday85%0.3% cancelled
- Tuesday87%0.0% cancelled
- Wednesday89%0.3% cancelled
- Thursday86%0.9% cancelled
- Friday85%0.0% cancelled
- Saturday88%0.6% cancelled
- Sunday80%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 aircraft73%
- Airline (crew, maintenance, cleaning, fueling)24%
- Air traffic control & airport congestion3%
- Extreme weather0%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)100%
- Extreme weather0%
- Air traffic control & airport congestion0%
- Security0%
ONT to SMF: common questions
- How often are ONT to SMF flights on time?
- 86% 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 Ontario to Sacramento cancelled?
- 0.3% of scheduled flights were cancelled (6 of 2,114).
- How long are typical delays?
- Across all flights the average arrival delay was 8 min (early arrivals count as zero). Flights that were late arrived 51 min behind schedule on average, and 4.1% of flights were an hour or more late.
- How long is taxi time at ONT?
- Flights on this route spent 10 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SMF to ONT — 84% on time
More flights from Ontario
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: ONT → SMF, nonstop flights by US airlines that report to the DOT. How we calculate this.