Santa Rosa to Seattle

What the Data Says About STS to SEA

The Santa Rosa to Seattle corridor (STS → SEA) covers roughly 618 miles and is served by 9 carriers, based on Bureau of Transportation Statistics reporting. Across 2,915 flights in the dataset, this route posts a 80.1% on-time rate with an average delay of 58.6 minutes when flights run late. Over the most recent 24 months of BTS data, 1,120 flights were recorded on this pairing — 11 cancelled (1.0%) and 1 diverted (0.1%). Those baseline metrics tell you what to expect before you book.

Having 9 carriers on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 2,915 total flights analyzed, the 80.1% on-time figure is statistically meaningful rather than a small-sample fluke. The 58.6-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, Sep 2023 posted the best performance on this corridor at 87% on-time, while Jun 2025 came in at 53% on-time — a 33-point gap between best and worst recent month. For travelers evaluating the STS to SEA route, the combination of a 80.1% on-time rate, 58.6-minute average delay, 1.0% recent cancellation rate, and 9 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.