DSM to STL flight delays
Des Moines, IA (DSM) St. Louis, MO (STL) · 259 miles
460 flights · January 2025 – August 2026 · the publishing regulator
89.93%
Arrived on time
Within 15 minutes of schedule
0.65%
Cancelled
Share of scheduled flights
69 min
When late, late by
Average across delayed arrivals
8 min
Delay per flight
Averaged over every flight flown
What the record says about this route
The two directions do not behave alike. STL to DSM arrives on time 9.5 points less 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.
Flights from Des Moines to St. Louis are among the most dependable in the record. A route this punctual is usually a short hop between airports with slots to spare.
This route does better than its own airport. Departures from DSM overall run 9.2 points less punctual than this particular one — so whatever congestion DSM has, this route is largely escaping it.
Only Southwest Airlines flies this route in the published record, so there is no choice to weigh — the route's figures and the airline's are the same figures.
Which airline should you fly on this route?
Over January 2025 – August 2026, Southwest Airlines arrived on time most often on DSM to STL. Flights ran closest to schedule in March and worst in August.
Every airline on DSM to STL
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 |
|---|---|---|---|---|---|
| Southwest Airlines | 460 | 89.93% | 0.65% | 69 min | A |
Month by month
Share of flights that arrived within 15 minutes of schedule, by month flown.
The return leg
STL to DSM St. Louis back to Des Moines 80.48% on time BOther routes from Des Moines
Common questions
Are flights from Des Moines to St. Louis usually delayed?
89.93% of flights on the DSM to STL route arrived within 15 minutes of schedule, so roughly 1 in every ten arrived late. That is better than the average route in this record.
Which airlines fly from Des Moines to St. Louis?
Only Southwest Airlines appears in the published record on this route, with 460 flights and 89.93% arriving on time.
How often are DSM to STL flights cancelled?
0.65% of scheduled flights did not operate — about 7 in every thousand. That is in the normal range.
What is the best month to fly Des Moines to St. Louis?
July, when 94.7% of flights arrived on time. The worst was August at 82.1%.
When DSM to STL flights are late, how late are they?
About 69 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 DSM to STL 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 →