C

SEA to MCI flight delays

Seattle, WA (SEA) Kansas City, MO (MCI) · 1,490 miles

1,131 flights · January 2025 – August 2026 · US Bureau of Transportation Statistics

77.74%

Arrived on time

Within 15 minutes of schedule

0.88%

Cancelled

Share of scheduled flights

55 min

When late, late by

Average across delayed arrivals

13 min

Delay per flight

Averaged over every flight flown

What the record says about this route

The season swings this route hard. In April it ran 38 points more punctual than in July — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.

The route has been getting better. The later months in the record run 16.6 points more punctual than the earlier ones, which usually means a schedule that was too tight has been given more room.

The two directions do not behave alike. MCI to SEA arrives on time 5.6 points more often than the outbound. Delay accumulates through the flying day, so whichever direction is scheduled later tends to carry the worse record — which is an argument for booking the morning departure if the choice exists.

The 2 airlines here are separated by under 3 points — close enough to call a tie. Choose on price and departure time.

Which airline should you fly on this route?

Over January 2025 – August 2026, Alaska Airlines arrived on time most often on SEA to MCI. Delta Air Lines was late most often. Flights ran closest to schedule in April and worst in July.

Every airline on SEA to MCI

Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.

Airline Flights On time Cancelled Avg delay Grade
Alaska Airlines 745 79.27% 0.54% 48 min C
Delta Air Lines 364 76.55% 1.65% 68 min C
Southwest Airlines 22 45.45% 0% 55 min

Month by month

Share of flights that arrived within 15 minutes of schedule, by month flown.

Jul 2025 peak 94 Jun 2026
On-time arrival rate, %

Common questions

Are flights from Seattle to Kansas City usually delayed?

77.74% of flights on the SEA to MCI route arrived within 15 minutes of schedule, so roughly 2 in every ten arrived late. That is about the same as the average route in this record.

Which airline is most on time from Seattle to Kansas City?

Alaska Airlines, at 79.27% on time across 745 flights. The least punctual on the route was Delta Air Lines at 76.55%.

How often are SEA to MCI flights cancelled?

0.88% of scheduled flights did not operate — about 9 in every thousand. That is in the normal range.

What is the best month to fly Seattle to Kansas City?

April, when 94.3% of flights arrived on time. The worst was July at 56.3%.

When SEA to MCI flights are late, how late are they?

About 55 minutes on average across the flights that arrived more than 15 minutes behind schedule.

What these figures do and do not tell you

Everything on this page is counted from the flights that actually operated on SEA to MCI during January 2025 – August 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.

A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.

Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →