Route · IAH → STL · 2020–2025 BTS data
Houston to St. Louis
The IAH–STL corridor (Houston, TX → St. Louis, MO) runs ahead of the national average, served by 13 carriers across roughly 667 miles.
Data updated 2026-06-13
- 80.3%
- On-time
- +1.3 pts
- vs US avg
- 78 min
- Delay when late
- 4,166
- Flights
Cancelled
1.1%
Best Month
Feb 2024 88%
Worst Month
Jul 2024 52%
Distance
667 mi
Carriers
13
Monthly Performance
Recent 24 months of route data.
| Period | Flights | Delayed | Cancelled | Diverted | Carriers |
|---|---|---|---|---|---|
| Dec 2025 | 33 | 8 | 0 | 0 | UA |
| Nov 2025 | 49 | 15 | 0 | 1 | OO,UA |
| Oct 2025 | 51 | 14 | 0 | 0 | UA |
| Sep 2025 | 50 | 10 | 0 | 0 | UA |
| Aug 2025 | 37 | 14 | 0 | 0 | OO,UA |
| Jul 2025 | 32 | 12 | 0 | 0 | OO,UA |
| Jun 2025 | 48 | 29 | 0 | 0 | OO,UA |
| May 2025 | 59 | 15 | 1 | 0 | UA |
| Apr 2025 | 90 | 25 | 0 | 1 | OO,UA |
| Mar 2025 | 34 | 5 | 0 | 0 | OO,UA |
| Feb 2025 | 38 | 7 | 0 | 0 | UA |
| Jan 2025 | 56 | 13 | 4 | 0 | UA |
| Dec 2024 | 58 | 13 | 1 | 0 | UA |
| Nov 2024 | 60 | 10 | 0 | 0 | OO,UA |
| Oct 2024 | 63 | 14 | 0 | 0 | UA |
| Sep 2024 | 60 | 16 | 1 | 0 | UA |
| Aug 2024 | 74 | 20 | 0 | 0 | OO,UA |
| Jul 2024 | 60 | 29 | 4 | 0 | UA |
| Jun 2024 | 84 | 36 | 0 | 0 | OO,UA |
| May 2024 | 43 | 20 | 0 | 0 | OO,UA |
| Apr 2024 | 60 | 16 | 0 | 0 | UA |
| Mar 2024 | 53 | 16 | 0 | 0 | UA |
| Feb 2024 | 56 | 7 | 0 | 1 | UA |
| Jan 2024 | 73 | 13 | 4 | 0 | OO,UA |
Cancellation Rate
1.1%
15 of 1,321 flights
Diversion Rate
0.2%
3 of 1,321 flights
Explore origin & destination
On-time and delay data for the airports this route connects.
IAH - Houston
Full on-time, delay-cause, and seasonal performance for Houston, TX.
Origin airport →STL - St. Louis
Full on-time, delay-cause, and seasonal performance for St. Louis, MO.
Destination airport →Compare the two airports
See IAH and STL side by side on delays, cancellations, and reliability.
Open comparison tool →Similar routes
Other BTS-tracked routes with comparable performance or trip length to IAH–STL.
Routes with a similar on-time rate
What the Data Says About IAH to STL
4,166 tracked flights put the IAH to STL pairing (Houston to St. Louis) at a 80.3% on-time rate, squarely in line with the wider network. Delays that do occur run 78.1 minutes on average. Across the 667-mile route and its 13 carriers, the trailing 24 months show 1.1% cancelled and 0.2% diverted (1,321 flights sampled).
The monthly split is wide on this route: Feb 2024 posted the strongest performance at 88% on-time, while Jul 2024 came in at just 52% - a 36-point swing worth factoring into travel timing.
Frequently Asked Questions
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Data source
Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.