St. Louis to Denver

What the Data Says About STL to DEN

The St. Louis to Denver corridor (STL → DEN) covers roughly 770 miles and is served by 27 carriers, based on Bureau of Transportation Statistics reporting. Across 20,999 flights in the dataset, this route posts a 79.9% on-time rate with an average delay of 71.2 minutes when flights run late. Over the most recent 24 months of BTS data, 7,523 flights were recorded on this pairing — 65 cancelled (0.9%) and 18 diverted (0.2%). Those baseline metrics tell you what to expect before you book.

Having 27 carriers on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 20,999 total flights analyzed, the 79.9% on-time figure is statistically meaningful rather than a small-sample fluke. The 71.2-minute average delay applies only to flights that actually ran late, so it is not the average wait across all departures — the majority of flights on this route depart on time under the BTS definition of a delay (15+ minutes past schedule).

Looking at recent months, Oct 2024 posted the best performance on this corridor at 87% on-time, while May 2024 came in at 66% on-time — a 22-point gap between best and worst recent month. For travelers evaluating the STL to DEN route, the combination of a 79.9% on-time rate, 71.2-minute average delay, 0.9% recent cancellation rate, and 27 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.