Half Marathons Near Boulder, CO
As of October 6, 2026, Crewable lists 14 upcoming half marathons near Boulder, CO from October 2026 to August 2027. The next is Breckenridge RunFest on October 10 in Breckenridge, CO. Registration is open for 12.
Sources: UltraSignup, RunSignUp, UTMB, race organizers and race websites
Race calendar
October 2026
8 racesCoffee Lovers Run 5K/10K/13.1 DENVER/AURORA
Centennial, COHalf Marathon10K+2Open until Oct 10from $30Halloween Trick or Trot Run 5K/10K/13.1 DENVER/AURORA
Centennial, COHalf Marathon10K+2Open until Oct 31from $30
November 2026
5 racesVeterans Day Freedom Run 5K/10K/13.1 DENVER/AURORA
Centennial, COHalf Marathon10K+2Open until Nov 14from $30
August 2027
1 raceQuick answers
What is the next half marathon near Boulder, CO?
Breckenridge RunFest, on Saturday, October 10, 2026, in Breckenridge, CO. Distances: Marathon, Half Marathon, 10K.
What is the closest half marathon to Boulder?
Louisville Trail Race in Louisville, CO, about 8 miles from Boulder, on November 14, 2026.
How many half marathons near Boulder, CO have open registration?
12 of the 14 list registration as open as of October 6, 2026, including Breckenridge RunFest, Coffee Lovers Run 5K/10K/13.1 DENVER/AURORA and Cookie Run 5K/10K/13.1 DENVER/AURORA.
What is the busiest month for half marathons near Boulder, CO?
October 2026, with 8 of the 14. November 2026 follows with 5.
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