What race distances can I run in Boulder?
Boulder has 5K (4). The 5K is usually the easiest entry point if you are new, and the links above jump straight to each distance.
Colorado · Race calendar
Running Races in Boulder, Colorado
Upcoming running races in and near Boulder, Colorado - 5Ks, 10Ks, half marathons and more, with dates, pricing, finish-time stats, start-line maps, and local run clubs to train with.
5 upcoming races · 1 with finish-time stats
By the numbers
The Biggest and Longest-Running
The Boulder races that stand out on the numbers: the biggest field, and the longest unbroken run of editions.
Sun, Sep 27, 2026Running for Children's Rights to Both Parents - 9 of 50 Half Marathons in 50 States Boulder, COFrom $500Register Sun, Sep 27, 2026Girls on the Run Rockies Boulderthon SoleMates 2026 Boulder, COFrom $25Register Thu, Nov 26, 2026Alpine Bank Boulder Thanksgiving Day 5K Boulder, COFrom $40Details Sun, May 2, 2027Emerge 5K Boulder, COFreeDetails Sat, Jun 12, 2027Alpha 5K Challenge Boulder, COPricing TBARegister
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 10, 2026.
Common Questions About Racing in Boulder
When is race season in Boulder?
September is the busiest month for races in Boulder, with 2 of the 5. If you are flexible on the date, that is the quickest way to narrow things down.
Where can I train for a race in Boulder?
Browse Boulder run clubs on RunSesh to find a training group at your pace.