Seattle to Portland

What the Data Says About SEA to PDX

The Seattle to Portland corridor (SEA → PDX) covers roughly 129 miles and is served by 19 carriers, based on Bureau of Transportation Statistics reporting. Across 35,578 flights in the dataset, this route posts a 83.7% on-time rate with an average delay of 55.3 minutes when flights run late. Over the most recent 24 months of BTS data, 10,050 flights were recorded on this pairing — 79 cancelled (0.8%) and 2 diverted (0.0%). Those baseline metrics tell you what to expect before you book.

Having 19 carriers on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 35,578 total flights analyzed, the 83.7% on-time figure is statistically meaningful rather than a small-sample fluke. The 55.3-minute average delay applies only to flights that actually ran late, so it is not the average wait across all departures — the majority of flights on this route depart on time under the BTS definition of a delay (15+ minutes past schedule).

Looking at recent months, Oct 2025 posted the best performance on this corridor at 88% on-time, while Jun 2024 came in at 67% on-time — a 21-point gap between best and worst recent month. For travelers evaluating the SEA to PDX route, the combination of a 83.7% on-time rate, 55.3-minute average delay, 0.8% recent cancellation rate, and 19 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.