On-Time Report

Routes › St. Louis (STL) › STL to DSM

Route · 12 months to July 2026

St. Louis to Des Moines: on-time record

St Louis Lambert International to Des Moines International

80.9%arrived on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report. Data through July 2026; this is a monthly history, not live flight status.

Flights from St. Louis (STL) to Des Moines (DSM) arrived on time 80.9% of the time in the 12 months to July 2026. Reporting carriers scheduled 403 flights on the route in that period, about 1.1 a day, a distance of 259 miles.

That is 4.9 points above the national on-time share of 76.0% for the same period and 4.1 points above the 76.8% recorded for all departures from STL. Flights that did arrive were 0.7 min late on average, and 0.5% of scheduled flights were cancelled (national: 1.8%).

Southwest Airlines is the only reporting carrier on the route, with 403 flights in the period.

By scheduled departure hour (local time at STL), flights leaving from 10 am to 11 am had the highest on-time share, 94.4%; those leaving from 10 pm to 11 pm had the lowest, 69.4%.

The on-time share is down 1.8 points on the previous 12 months (82.7%); cancellations moved from 0.7% to 0.5%.

Of the delay minutes that carriers assigned to a BTS cause category on this route, late-arriving aircraft 62%, air carrier 22% and national aviation system 13%.

80.9%arrived on timenational 76.0%
0.7 minaverage arrival delayearly arrivals count as negative; national 8.1 min
0.5%cancellednational 1.8%
34flights a month403 in 12 months · 259 miles
Every scheduled STL to DSM flight by a reporting carrier, August 2025 to July 2026.

Airlines on the route compared

Reporting carrierFlightsShareOn timeAvg arrival delayCancelled
WN Southwest Airlines403100%80.9%0.7 min0.5%

Carriers with at least 24 flights in the 12 months to July 2026. The on-time pill is green when a carrier is at or above the route's overall share. Regional carriers operate flights sold under larger airlines' brands; BTS lists the carrier that operated the flight.

Compared with the airports and the nation

MeasureSTL to DSMAll departures from STLAll arrivals at DSMAll reported flights
Arrived on time80.9%76.8%73.5%76.0%
Arrived 15+ minutes late18.1%21.7%23.9%21.9%
Cancelled0.5%1.3%2.4%1.8%
Diverted0.5%0.3%0.3%0.3%
Average arrival delay0.7 min7.8 min10.9 min8.1 min
Delay minutes per 100 flights9161,5961,8941,684
Scheduled flights40363,31815,5847,043,858

12 months to July 2026. Delay minutes count late arrivals only (an early arrival is zero), so the per-100-flights row is a normalised total rather than an average of early and late.

The return direction, DSM to STL, recorded 88.6% on time across 403 flights in the same period.

Month by month

100%columns start at 40%
Share of scheduled STL to DSM flights that arrived on time, Aug 2023 to Jul 2026. Green columns are at or above the national figure for that month (the dark tick), amber below it, red more than eight points below.

Year on year: on time 80.9% against 82.7% (−1.8 pts), cancelled 0.5% against 0.7%, flights 403 against 678.

By scheduled departure hour

On-time share:under 62%6270768288% and over
Share of flights that arrived on time, by the hour they were scheduled to leave STL (local time), 12 months to July 2026. Faded cells have few flights. Hover or tap a cell for counts.

Delay causes

BTS cause categoryShare of delay minutesNationalMinutes
Air carrier22.4%33.3%746
Late-arriving aircraft62.0%39.7%2,068
National Aviation System12.5%20.7%415
Extreme weather3.1%6.1%104
Security0.0%0.1%0
3,333 delay minutes on 73 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Seasonality

Calendar monthFlightsOn timeCancelledAvg arrival delayYears in sample
Jan17575.4%4.6%4.7 min3
Feb15885.4%0.0%-2.2 min3
Mar12277.0%1.6%3.1 min3
Apr11275.9%0.0%7.9 min2
May11469.3%0.9%13.9 min2
Jun11179.3%0.0%5.7 min2
Jul11571.3%0.0%10.8 min2
Aug17181.9%0.0%5.4 min3
Sep16685.5%0.0%-1.0 min3
Oct17289.0%0.0%0.1 min3
Nov16985.8%1.2%-2.1 min3
Dec17976.5%0.0%4.6 min3

Each calendar month summed across the 36 months on file, so most rows combine three years. The pill compares the month with the route's own 12-month share.

Other routes from St. Louis (STL)

RouteCitiesFlightsOn timeAvg arrival delayCancelled
STL–ATLSt. Louis to Atlanta3,68483.1%-0.3 min1.7%
STL–DENSt. Louis to Denver3,67675.1%10.4 min0.3%
STL–ORDSt. Louis to Chicago3,09069.9%19.0 min3.6%
STL–LGASt. Louis to New York2,62471.6%8.9 min3.6%
STL–MCOSt. Louis to Orlando2,52076.9%6.6 min0.9%
STL–DCASt. Louis to Washington2,41670.9%12.3 min2.6%
STL–DFWSt. Louis to Dallas/Fort Worth2,38172.4%19.0 min3.3%
STL–PHXSt. Louis to Phoenix2,31574.2%13.1 min0.5%

All 65 routes and the airport record for STL · airport record for DSM

Questions and answers

How often are flights from St. Louis to Des Moines on time?

80.9% of the 403 flights scheduled from STL to DSM in the 12 months to July 2026 arrived less than 15 minutes after their scheduled time. The national share for the same period was 76.0%. Cancelled and diverted flights count as not on time.

Which airline has the highest on-time share from STL to DSM?

Southwest Airlines is the only reporting carrier with at least 60 flights on the route in the period, so there is no comparison to make.

What causes delays between St. Louis and Des Moines?

For flights that arrived 15 or more minutes late, carriers attributed the delay minutes as follows: late-arriving aircraft 62%, air carrier 22%, national aviation system 13%, extreme weather 3%, security 0%. The categories are the carriers' own reports to BTS; weather that slows the wider system is usually recorded under the National Aviation System rather than extreme weather.

What time of day has the highest on-time share from STL?

Flights scheduled to leave STL from 10 am to 11 am arrived on time 94.4% of the time, the highest of any hour with enough flights to compare. The lowest was 10 pm to 11 pm at 69.4%. Delays tend to build through the day as late aircraft carry over to later flights.

Is it getting better?

The on-time share for the 12 months to July 2026 was 80.9%, down 1.8 points on the previous 12 months (82.7%). The monthly chart on this page shows each of the last 36 months. Across those months, October had the highest on-time share (89.0%) and May the lowest (69.3%).

Where does this data come from?

Every figure is computed from the Bureau of Transportation Statistics Reporting Carrier On-Time Performance files, which list each scheduled domestic flight by the carriers required to report. This page covers August 2023 to July 2026. It shows totals and averages only; it is not a live flight-status service.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987 to present), monthly files August 2023 to July 2026, a US government work in the public domain. Figures are totals and averages over all scheduled flights by reporting carriers on the route; no individual flight or aircraft is identified. Times are local to the departure airport. The load factor and passenger counts from the BTS T-100 series are not included in this edition. See the methodology; report processing errors through corrections.