SEA to MSO flight delays & on-time performance
Nonstop flights from Seattle–Tacoma International Airport to Missoula Montana Airport · 389 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at SEA or MSO right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Seattle (SEA) to Missoula (MSO) arrived on time 84% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.8% were cancelled, and 4% arrived an hour or more late.
- Alaska Airlines was the most punctual airline here (84% on time); SkyWest Airlines was the least (83%).
- Departures scheduled around 8am did best (88% on time); around 9am did worst (74%).
- Wednesday was the most reliable day to fly (89% on time) and Friday the least (78%).
- The largest source of delay minutes was late-arriving aircraft (38%).
Which airline is most on time from SEA to MSO?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Alaska Airlines | 84% | 0.9% | 9 min | 3.6% | 539 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 83% | 0.0% | 8 min | 3.4% | 87 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 8am88%52 flights
- 9am74%35 flights
- 12pm88%143 flights
- 1pm83%163 flights
- 9pm82%230 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday82%1.1% cancelled
- Tuesday89%0.0% cancelled
- Wednesday89%1.1% cancelled
- Thursday81%2.2% cancelled
- Friday78%1.1% cancelled
- Saturday85%0.0% cancelled
- Sunday82%0.0% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft38%
- Airline (crew, maintenance, cleaning, fueling)36%
- Air traffic control & airport congestion16%
- Extreme weather10%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Air traffic control & airport congestion60%
- Extreme weather40%
- Airline (crew, maintenance, cleaning, fueling)0%
- Security0%
SEA to MSO: common questions
- How often are SEA to MSO flights on time?
- 84% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Seattle to Missoula cancelled?
- 0.8% of scheduled flights were cancelled (5 of 626).
- How long are typical delays?
- Across all flights the average arrival delay was 9 min (early arrivals count as zero). Flights that were late arrived 46 min behind schedule on average, and 3.5% of flights were an hour or more late.
- How long is taxi time at SEA?
- Flights on this route spent 21 min taxiing from the gate to takeoff on average.
Related routes
Return trip: MSO to SEA — 82% on time
More flights from Seattle
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: SEA → MSO, nonstop flights by US airlines that report to the DOT. How we calculate this.