Race calendar · September 2027 · Colorado
Every Half Marathon in Colorado in September 2027, all 5 of them, sorted by date. Dates, entry fees, finish-time stats from past results, and start-line maps.
What the field actually runs
How we calculate these stats: RunSesh calculates these figures from the most recent published results of past editions, sourced from RunSignup. We show aggregates only: field size, winning and median times, and the cutoff. We never publish individual finisher tables. Last updated Oct 22, 2026.
When in September
Half marathons are not spread evenly across September. Here is how the calendar actually falls, weekend by weekend, which is the part worth knowing before you book a trip or plan a taper around one.
By the numbers
The largest field of any September Half Marathon in Colorado, from the most recent published results.
Across the 4 of these September half marathons with published results from past editions, the median finisher ran 2:29:34, and the median winning time was 1:22:37. So anything under 2:29:34 puts you in the faster half of a typical field. That is the middle of these RunSignup fields, walkers and charity entrants included, not a national average.
The median one finished 82 runners, across the 4 of these September half marathons with published results from past editions. Most are far smaller than the big-city events people picture, which means less crowding at the start and a friendlier field, with a last recorded finisher at 3:46:41.
Yes, one race around Colorado gets you off the pavement: 1 is a trail race.
