Colorado Running Races

472 upcoming races across Colorado in the next 12 months, from local 5Ks to marathons and ultras. Updated nightly. Want filters, maps, and radius search? Open Colorado in the Race Finder.

By distance: Marathons · Half Marathons · 5K Races · 10K Races · Ultras

By city: Denver · Colorado Springs · Centennial · Fort Collins · Littleton · Arvada · Westminster · Aurora · Pueblo · Grand Junction

Racing in Colorado: what the calendar looks like

There are 472 races on the Colorado calendar over the next 12 months, which works out to roughly 9 every weekend. September is the busiest month with 155 races; March is the quietest with 14. The busiest places to race are Denver (51), Colorado Springs (41), Centennial (28).

Of those, 304 offer a 5K, 134 offer a 10K and 126 offer a Half Marathon. The next marathon is Denver, CO Galloway Training Program on September 5 in Denver. The next half marathon is Denver, CO Galloway Training Program on September 5.

By race count Colorado ranks 15th of 51 states.

Races by month

September 2026

October 2026

November 2026

December 2026

January 2027

February 2027

March 2027

April 2027

May 2027

June 2027

July 2027

August 2027

Planning a race

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