Best Time to Fly SEA to MSO: On-Time Stats by Hour & Airline
Seattle/Tacoma International → Missoula Montana
Data through July 2026 · Last updated October 18, 2026
626 flights were scheduled from Seattle (SEA) to Missoula (MSO) in the last 12 months, and 83.5% of those that flew arrived on time, 5.9 points above the US average of 77.6%.
Among 2 airlines, Alaska Airlines led with 83.7% on time and SkyWest Airlines was last with 82.8%.
Over 24 months, Wednesday was the most reliable day (81% on time) and August the worst month (55%).
The cancellation rate was 0.8% (US average 1.8%).
SEA to MSO on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| Alaska Airlines | 83.7% | 47 min | 0.9% | 539 |
| SkyWest Airlines | 82.8% | 37 min | 0.0% | 87 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SEA to MSO
On-time arrival % by scheduled departure hour (local time), 977 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 8am–9am | 88.5% | 0.0% | 52 |
| 9am–10am | 74.3% | 0.0% | 35 |
| 11am–12pm | 57.0% | 0.7% | 301 |
| 12pm–1pm | 82.0% | 1.1% | 186 |
| 1pm–2pm | 83.2% | 0.6% | 163 |
| 2pm–3pm | Limited data | 10 | |
| 9pm–10pm | 82.5% | 0.9% | 230 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SEA to MSO
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | Limited data | 19 | ||
| Christmas & New Year (Dec 20 - Jan 3) | 68.2% | -7.4 pts | 0.0% | 45 |
| Summer peak (Jun 15 - Aug 15) | 69.5% | -6.2 pts | 0.0% | 191 |
| All other days | 75.6% | — | 1.0% | 722 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).