Route · IAH → STL · 2020–2025 BTS data
Houston to St. Louis
According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), IAH to STL (Houston to St. Louis) ranks #2838 of 4927 tracked domestic routes by total flights (most flights = #1).
Data updated 2026-06-13
- 80.3%
- On-time
- +1.3 pts
- vs US avg
- 78 min
- Delay when late
- 4,166
- Flights
- #2838 of 4927
- Corpus placement
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 |
IAH–STL seasonal on-time pattern
Best: February (86.3%) · weakest: June (68.6%)
Strongest calendar month
February
86.3% on-time · ~68 flights/mo
Busiest calendar month
January
~75 flights/mo avg
Weakest calendar month
June
68.6% on-time · ~71 flights/mo
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.
IAH on-time profileSTL - St. Louis
Full on-time, delay-cause, and seasonal performance for St. Louis, MO.
STL on-time profileCompare the two airports
See IAH and STL side by side on delays, cancellations, and reliability.
Compare IAH vs STLOrigin-hub reliability standing
Mid-pack among IAH departures
From IAH, this corridor sits with 79 other 75–85% on-time routes out of 102 tracked departures, not the hub's reliability leaders (17 at ≥85%) and not the softest ( 6 below 75%). Destination: St. Louis · fleet on-time rank #3021 of 4927.
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.
On the multi-year calendar, IAH–STL peaks in February at 86.3% on-time while January carries the heaviest traffic (~75 flights per month) ; the softest month is June at 68.6%, a 17.7-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.
Frequently Asked Questions
Where does IAH to STL rank among US routes by traffic? ▼
How often are flights delayed from IAH to STL? ▼
What is the cancellation rate for IAH to STL? ▼
How far is the flight from IAH to STL? ▼
When is the best time to fly from IAH to STL? ▼
Airports on this route
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.
Using IAH–STL data
IAH–STL is mid-pack at 80.3% on-time; month and carrier mix move more than the corridor headline.
- Compare IAH and STL airport profiles: delay causes and top routes differ even on the same corridor. IAH airport
- If your dates flex, February (86.3% on-time) beats June (68.6%) on this corridor. Seasonal chart
- 4 other routes post a similar 80.3% on-time rate; compare before you commit to this pairing. Similar routes
On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.
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.