Race calendar · December 2026 · Colorado
Every 5K in Colorado in December 2026, all 19 of them, sorted by date. Dates, entry fees, finish-time stats from past results, and start-line maps.
19 5K races in December 2026
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 Sep 22, 2026.
When in December
5K races do not spread evenly across December. The busiest weekend is December 12 and December 13, with 8 of them. Another 1 fall on a weekday.
By the numbers
The December 5K races that stand out on the numbers: the biggest field, and the longest unbroken run of editions.
The busiest weekend in Colorado is December 12 and December 13, with 8 5K races on those two days, and the single busiest day is Saturday, December 12 with 7. Another 1 fall on a weekday, which is worth knowing if you are traveling for one.
As early as you can. 9 of these December 5K races already have a price increase on the calendar, and 17 are open for entry right now. Another 2 have published an opening date and have not opened yet.
The typical entry is $30, with paid entries running from $15 up to $50. Entry fees climb as race day gets closer, so the same race is usually cheapest the week it opens.
Across the 10 of these December 5K races with published results from past editions, the median finisher ran 35:58, and the median winning time was 17:06. So anything under 35:58 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 335 runners, across the 10 of these December 5K races 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 1:12:19.
Yes, 3 races around Colorado get you off the pavement: 1 is a trail race, and 2 mix road and trail. Surfaces are not always published, so it is worth checking a specific race before you register.
November and January sit either side of December, which is where most people look next when a date does not fit.
