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 December
The December Race Weekends
10K races are not spread evenly across December. 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.
Dec 5 - Dec 63
Dec 12 - Dec 136
Dec 19 - Dec 205
Dec 26 - Dec 275
By the numbers
The Biggest Field
The largest field of any December 10K in Washington, from the most recent published results.
Common Questions About Running a December 10K in Washington
When in December are most 10K races held?
The busiest weekend in Washington is December 12 and December 13, with 6 of them. Every one of them is on a Saturday or a Sunday.
What is a good 10K time?
Across the 7 of these December 10K races with published results from past editions, the median finisher ran 1:00:14, and the median winning time was 43:56. So anything under 1:00:14 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 December 10K field?
The median one finished 6 runners, across the 7 of these December 10K 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 1:28:02.
Are there trail 10K races in Washington in December?
Yes, one race around Washington gets you off the pavement: 1 mixes road and trail.