Seattle to Walla Walla

What the Data Says About SEA to ALW

The Seattle to Walla Walla corridor (SEA → ALW) covers roughly 213 miles and is served by 2 carriers, based on Bureau of Transportation Statistics reporting. Across 2,216 flights in the dataset, this route posts a 87.3% on-time rate with an average delay of 54.9 minutes when flights run late. Over the most recent 24 months of BTS data, 1,277 flights were recorded on this pairing — 40 cancelled (3.1%) and 3 diverted (0.2%). Those baseline metrics tell you what to expect before you book.

Having 2 carriers on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 2,216 total flights analyzed, the 87.3% on-time figure is statistically meaningful rather than a small-sample fluke. The 54.9-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, Nov 2023 posted the best performance on this corridor at 97% on-time, while Sep 2024 came in at 64% on-time — a 32-point gap between best and worst recent month. For travelers evaluating the SEA to ALW route, the combination of a 87.3% on-time rate, 54.9-minute average delay, 3.1% recent cancellation rate, and 2 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.