When in October are most half marathons held?
The busiest weekend in Colorado is October 2 and October 3, with 4 of them, 2 of those on Saturday, October 2. Every one of them is on a Saturday or a Sunday.
Race calendar · October 2027 · Colorado
Half Marathons in Colorado in October 2027
Every Half Marathon in Colorado in October 2027, all 6 of them, sorted by date. Dates, entry fees, finish-time stats from past results, and start-line maps.
What the field actually runs
October Half Marathons, By the Numbers
2:19:31Median finish time
1:17:48Median winning time
166Median field size
6October half marathons with published results
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 Nov 12, 2026.
When in October
The October Race Weekends
Half marathons are not spread evenly across October. 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 Biggest Field
The largest field of any October Half Marathon in Colorado, from the most recent published results.
Colorado Half Marathons by City in October
All Half Marathons in Colorado in October
6 total Sat, Oct 2, 2027Colorado Springs Marathon, Half, 5K, and Kids K Colorado Springs, COFrom $65Details Sat, Oct 2, 2027Spooky Sprint - Denver Denver, COFrom $52Details Sun, Oct 3, 2027Windsor Marathon, Half Marathon, 10k, 5k & 1 Mile Run Windsor, COFrom $90Details Sun, Oct 3, 2027Spooky Sprint - Colorado Springs Colorado Springs, COPricing TBADetails Sun, Oct 10, 2027Westy Half & 5k Westminster, COFrom $64Details Sun, Oct 31, 2027All-Out Kooky-Spooky Golden, COFrom $65Details
Common Questions About Running an October Half Marathon in Colorado
What is a good Half Marathon time?
Across the 6 of these October half marathons with published results from past editions, the median finisher ran 2:19:31, and the median winning time was 1:17:48. So anything under 2:19:31 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.
How big is a typical October Half Marathon field?
The median one finished 166 runners, across the 6 of these October 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 3:42:15.
Are there trail half marathons in Colorado in October?
Yes, one race around Colorado gets you off the pavement: 1 mixes road and trail.