Route · ONT → SEA · 2020–2025 BTS data
Ontario to Seattle
The ONT–SEA corridor (Ontario, CA → Seattle, WA) runs ahead of the national average, served by 17 carriers across roughly 956 miles.
Data updated 2026-06-13
- 87.1%
- On-time
- +8.1 pts
- vs US avg
- 69 min
- Delay when late
- 12,860
- Flights
Cancelled
1.2%
Best Month
Oct 2024 94%
Worst Month
Feb 2025 81%
Distance
956 mi
Carriers
17
Monthly Performance
Recent 24 months of route data.
| Period | Flights | Delayed | Cancelled | Diverted | Carriers |
|---|---|---|---|---|---|
| Dec 2025 | 200 | 36 | 2 | 1 | F9,AS,OO |
| Nov 2025 | 211 | 26 | 7 | 0 | OO,F9,AS |
| Oct 2025 | 200 | 30 | 2 | 0 | AS,OO,F9 |
| Sep 2025 | 213 | 25 | 1 | 1 | OO,DL,F9,AS |
| Aug 2025 | 266 | 43 | 2 | 0 | OO,F9,AS,DL |
| Jul 2025 | 302 | 54 | 9 | 0 | AS,OO,F9 |
| Jun 2025 | 266 | 39 | 1 | 0 | AS,OO,F9 |
| May 2025 | 258 | 39 | 2 | 1 | AS,OO,F9 |
| Apr 2025 | 202 | 19 | 0 | 0 | F9,OO,AS |
| Mar 2025 | 183 | 26 | 0 | 2 | AS,OO,F9 |
| Feb 2025 | 147 | 28 | 4 | 0 | AS,OO,F9 |
| Jan 2025 | 166 | 31 | 3 | 1 | AS,OO,F9 |
| Dec 2024 | 174 | 23 | 1 | 2 | AS,F9,OO |
| Nov 2024 | 227 | 22 | 1 | 0 | OO,AS,F9 |
| Oct 2024 | 209 | 12 | 0 | 0 | AS,OO,F9 |
| Sep 2024 | 224 | 40 | 0 | 0 | OO,AS,F9 |
| Aug 2024 | 255 | 42 | 3 | 0 | AS,F9,OO |
| Jul 2024 | 276 | 48 | 3 | 0 | AS,F9,OO |
| Jun 2024 | 270 | 51 | 1 | 0 | AS,F9,OO |
| May 2024 | 254 | 35 | 1 | 0 | AS,F9,OO |
| Apr 2024 | 200 | 14 | 0 | 0 | AS,DL,OO |
| Mar 2024 | 152 | 15 | 0 | 0 | AS,DL |
| Feb 2024 | 133 | 10 | 0 | 0 | AS,DL |
| Jan 2024 | 143 | 10 | 17 | 0 | AS,DL |
Cancellation Rate
1.2%
60 of 5,131 flights
Diversion Rate
0.2%
8 of 5,131 flights
Explore origin & destination
On-time and delay data for the airports this route connects.
ONT - Ontario
Full on-time, delay-cause, and seasonal performance for Ontario, CA.
Origin airport →SEA - Seattle
Full on-time, delay-cause, and seasonal performance for Seattle, WA.
Destination airport →Compare the two airports
See ONT and SEA side by side on delays, cancellations, and reliability.
Open comparison tool →Similar routes
Other BTS-tracked routes with comparable performance or trip length to ONT–SEA.
Routes with a similar on-time rate
What the Data Says About ONT to SEA
Ontario to Seattle (ONT to SEA) is one of the more dependable pairings in the BTS On-Time Performance dataset: a 87.1% on-time rate across 12,860 flights, with delays that do happen averaging 69.4 minutes. The corridor runs roughly 956 miles and is served by 17 carriers. Over the most recent 24 months, 60 of 5,131 flights were cancelled (1.2%) and 8 diverted (0.2%).
Monthly performance varies moderately here: Oct 2024 was the strongest month at 94% on-time versus Feb 2025 at 81%, a 13-point difference.
Frequently Asked Questions
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Data source
Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.