Ontario (ONT) to Portland (PDX): On-Time Performance
Data through May 2026
Ontario (ONT) to Portland (PDX) effectively runs on two schedules. In April 2025, 100% of arrivals were on time; in October 2024 that fell to 73% — a 28-point seasonal swing. Across the full period the route averages 87% on-time against a national 78%. Morning departures also hold up better than evening ones (92% vs 82%), which matters most in the rough months.
- On-time
- 87%
- arrived <15 min late
- Avg delay
- 8 min
- completed flights
- Cancelled
- 0.9%
- Flights/day
- 1.4
- last 12 months
- Duration
- 2h 23m
- scheduled
- Distance
- 838 mi
Best airline from ONT to PDX
3 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| Alaska Airlinesmost reliable | 91% | 6 min | 1.0% | 601 |
| SkyWest Airlines | 91% | 6 min | 0.6% | 311 |
| Frontier Airlines | 75% | 13 min | 1.0% | 294 |
Monthly on-time trend
Best time to fly from ONT to PDX
Aim for departures around 6 a.m. (97% on-time); avoid 3 p.m. departures (73%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 88% | 7 min |
| Tuesday | 87% | 5 min |
| Wednesday | 90% | 5 min |
| Thursday | 83% | 11 min |
| Friday | 88% | 8 min |
| Saturdaybest | 90% | 8 min |
| Sunday | 86% | 9 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft52%
- Airline operations29%
- National airspace system17%
- Weather2%
Frequently asked questions
- How often are flights from ONT to PDX delayed?
- 13% of ONT–PDX flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 8 minutes.
- Which airline is most reliable from ONT to PDX?
- Alaska Airlines has the best on-time record on this route at 91%, based on 601 flights. 3 airlines flew ONT–PDX frequently enough to compare in this period.
- What is the best time of day to fly from ONT to PDX?
- Departures around 6 a.m. have the best record (97% on-time), while departures around 3 p.m. have the worst (73%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from ONT to PDX?
- The scheduled ONT–PDX flight time averages 2h 23m over 838 miles. Actual arrival times vary — flights on this route land 15+ minutes late 13% of the time.
- How often are ONT to PDX flights cancelled?
- 0.9% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from ONT to PDX?
- October 2024 was the roughest month in this dataset, with only 73% of arrivals on time. The best was April 2025 at 100%. If your dates are flexible, that 28-point gap is worth planning around.
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Based on 1,228 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.