Missoula to Seattle

What the Data Says About MSO to SEA

The Missoula to Seattle corridor (MSO → SEA) covers roughly 389 miles and is served by 2 carriers, based on Bureau of Transportation Statistics reporting. Across 2,926 flights in the dataset, this route posts a 80% on-time rate with an average delay of 60.7 minutes when flights run late. Over the most recent 24 months of BTS data, 1,516 flights were recorded on this pairing — 20 cancelled (1.3%) 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 2,926 total flights analyzed, the 80% on-time figure is statistically meaningful rather than a small-sample fluke. The 60.7-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, Oct 2022 posted the best performance on this corridor at 93% on-time, while Dec 2022 came in at 57% on-time — a 36-point gap between best and worst recent month. For travelers evaluating the MSO to SEA route, the combination of a 80% on-time rate, 60.7-minute average delay, 1.3% recent cancellation rate, and 2 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.