Best Time to Fly MSO to SEA: On-Time Stats by Hour & Airline
Missoula Montana → Seattle/Tacoma International
Data through July 2026 · Last updated October 18, 2026
646 flights were scheduled from Missoula (MSO) to Seattle (SEA) in the last 12 months, and 82.3% of those that flew arrived on time, 4.7 points above the US average of 77.6%.
SkyWest Airlines was the most punctual of the 2 airlines on the route at 85.2%, while Alaska Airlines trailed at 81.8%.
April has been the best month (88% on time) and Sunday the weakest day of the week (72%).
0.9% of flights were cancelled, versus 1.8% nationally.
MSO to SEA 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 |
|---|---|---|---|---|
| SkyWest Airlines | 85.2% | 43 min | 0.0% | 108 |
| Alaska Airlines | 81.8% | 51 min | 1.1% | 538 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly MSO to SEA
On-time arrival % by scheduled departure hour (local time), 997 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 6am–7am | 85.2% | 0.0% | 142 |
| 7am–8am | 94.2% | 2.2% | 89 |
| 11am–12pm | 80.8% | 0.0% | 52 |
| 1pm–2pm | 89.3% | 0.0% | 56 |
| 2pm–3pm | 73.0% | 1.1% | 273 |
| 3pm–4pm | 75.4% | 0.0% | 65 |
| 4pm–5pm | 73.6% | 1.6% | 258 |
| 5pm–6pm | 72.6% | 0.0% | 62 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on MSO to SEA
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) | 76.7% | -3.2 pts | 2.3% | 44 |
| Summer peak (Jun 15 - Aug 15) | 70.8% | -9.1 pts | 0.0% | 192 |
| All other days | 80.0% | — | 1.1% | 742 |
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).