Seattle (SEA) to Kansas City (MCI): On-Time Performance
Data through July 2026
The calendar drives reliability on SEA–MCI. April 2026 flights landed on schedule 92% of the time, but July 2025 dropped to 56% — a gap of 36 points. Across the full period the route averages 78% on-time against a national 78%. Morning departures also hold up better than evening ones (86% vs 75%), which matters most in the rough months.
- On-time
- 78%
- arrived <15 min late
- Avg delay
- 13 min
- completed flights
- Cancelled
- 0.9%
- Flights/day
- 3.1
- last 12 months
- Duration
- 3h 31m
- scheduled
- Distance
- 1,490 mi
Best airline from SEA to MCI
3 airlines flew this route regularly between 2024-07 and 2026-07.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| Alaska Airlinesmost reliable | 79% | 10 min | 0.5% | 1,587 |
| Delta Air Lines | 77% | 16 min | 1.7% | 759 |
| Southwest Airlines | 58% | 25 min | 0.0% | 60 |
Monthly on-time trend
Best time to fly from SEA to MCI
Aim for departures around 7 a.m. (90% on-time); avoid 12 p.m. departures (49%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 78% | 11 min |
| Tuesdaybest | 81% | 13 min |
| Wednesday | 78% | 10 min |
| Thursday | 77% | 14 min |
| Friday | 78% | 13 min |
| Saturday | 78% | 12 min |
| Sunday | 75% | 15 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft32%
- Airline operations48%
- National airspace system16%
- Weather4%
Frequently asked questions
- How often are flights from SEA to MCI delayed?
- 22% of SEA–MCI flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 13 minutes.
- Which airline is most reliable from SEA to MCI?
- Alaska Airlines has the best on-time record on this route at 79%, based on 1,587 flights. 3 airlines flew SEA–MCI frequently enough to compare in this period.
- What is the best time of day to fly from SEA to MCI?
- Departures around 7 a.m. have the best record (90% on-time), while departures around 12 p.m. have the worst (49%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from SEA to MCI?
- The scheduled SEA–MCI flight time averages 3h 31m over 1,490 miles. Actual arrival times vary — flights on this route land 15+ minutes late 22% of the time.
- How often are SEA to MCI flights cancelled?
- 0.9% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, at or below the national rate of 1.6%.
- What is the worst month to fly from SEA to MCI?
- July 2025 was the roughest month in this dataset, with only 56% of arrivals on time. The best was April 2026 at 92%. If your dates are flexible, that 36-point gap is worth planning around.
Explore related pages
More routes from SEA
Other ways to fly to Kansas City (MCI)
Related guides
Based on 2,406 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.