Seattle to San Jose

What the Data Says About SEA to SJC

The Seattle to San Jose corridor (SEA → SJC) covers roughly 696 miles and is served by 19 carriers, based on Bureau of Transportation Statistics reporting. Across 26,361 flights in the dataset, this route posts a 85% on-time rate with an average delay of 56.7 minutes when flights run late. Over the most recent 24 months of BTS data, 8,992 flights were recorded on this pairing — 81 cancelled (0.9%) 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 26,361 total flights analyzed, the 85% on-time figure is statistically meaningful rather than a small-sample fluke. The 56.7-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, Jan 2025 posted the best performance on this corridor at 91% on-time, while Jul 2025 came in at 73% on-time — a 18-point gap between best and worst recent month. For travelers evaluating the SEA to SJC route, the combination of a 85% on-time rate, 56.7-minute average delay, 0.9% recent cancellation rate, and 19 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.