2024-2025 Colorado Half Marathons Race Calendar

Colorado Half Marathons by Date

Browse all Colorado Half Marathon 2024 and 2025 by month and by city below.

For each race, you’ll find the history of the half marathon and the course, the most recent year’s course maps, elevation profiles, runner reviews, pricing, and how to sign up. When you view a race, you might also find contact info if you’re having problems with your registration or need to contact the race directors.

We dedicated dozens of hours every month searching for races to include in the Colorado Half Marathons calendar.

If you happen to see any half marathon not included, contact us at info@halfmarathons.net to submit your race.

Check beneath the Colorado half marathon calendar for answers to frequently asked questions.

Upcoming 2024 Colorado Half Marathons

July 2024

Thu Jul 4 July 4th ROCK-IT Run Half Marathon & 5k Castle Rock CO
Thu Jul 4 Longmont Half Marathon & 5K Longmont CO
Sat Jul 13 All-Out Dog Days Half Marathon 10K & 5K Westminster CO
Sat Jul 13 Aspen Valley Marathon Half Marathon & 5k Aspen CO
Sat Jul 20 Prairie Dog Half Marathon 10K & 5K Castle Rock CO
Colorado Springs Half Marathon Featured

August 2024

Boulderthon in Boulder Colorado Half Marathon 2024

September 2024

Sun Sep 1 Calarat Challenge Trail Running Festival Half Marathon 10k & 5k Jamestown CO
Mon Sep 2 Labor Day Half Marathon Parker CO
Sat Sep 7 Black Squirrel Half Marathon Bellvue CO
Sat Sep 7 Sloan's Lake Search Party Marathon & Half Marathon Hourly Loop Race Denver CO
Sat Sep 14 All-Out Fall Fest Marathon Half Marathon 10K & 5K Westminster CO
Sat Sep 14 Bergen Peak Half Marathon Evergreen CO
Sat Sep 14 Trail Sisters Women's Half Marathon Buena Vista CO
Sun Sep 15 Nun Run Half Marathon 10k & 5k Centennial CO
Sat Sep 21 Autumn Color Run Half Marathon 10k 5k & 1M Buena Vista CO
Sat Sep 21 Beulah Challenge Half Marathon 10k & 5k Beulah CO
Sat Sep 21 John Wayne Grit Series – Ridgway Half Marathon & 5k Ridgway CO
Sat Sep 21 Run the Rockies Half Marathon & 10k Frisco CO
Sat Sep 21 Snow Mountain Ranch Trail Festival Half Marathon Granby CO
Sun Sep 22 Fall Equinox Marathon Half Marathon & 5M Fort Collins CO
Sun Sep 22 Red Feather Trail Jamboree 50k & Half Marathon Red Feather Lakes CO
Sun Sep 22 Sunlight Showdown Half Marathon Glenwood Springs CO
Sat Sep 28 Colorado Springs Marathon Half Marathon & 5k Colorado Springs CO
Sat Sep 28 Deep Creek Trail Half Marathon Telluride CO
Sat Sep 28 Golden Leaf Half Marathon Aspen CO
Sat Sep 28 Louisville Trail Race Half Marathon 10k & 5k Louisville CO
Sat Sep 28 Pioneer Prairie Dog Half Marathon 10K & 5K Westminster CO
Sat Sep 28 The Rad Dirt Fest 50k & Half Marathon Trinidad CO
Sun Sep 29 Bear Chase Race Half Marathon & 10k Lakewood CO
Sun Sep 29 Boulderthon: Downtown Boulder Marathon Half Marathon & 5k Boulder CO
Mon Sep 30 Center of the Nation Series – Day 1 Marathon & Half Marathon Sterling CO
TBD Sep Breck Crest Mountain Marathon Half Marathon & 10k Breckenridge CO
TBD Sep Black Squirrel Half Marathon Fort Collins CO
TBD Sep Ned Ned Run Half Marathon 10k & 5k Nederland CO
TBD Sep Mountain RATS 55k Marathon & Half Marathon Eagle CO
TBD Sep Adams Half & 5k Brighton CO

October 2024

November 2024

December 2024

Sat Dec 7 All-Out Fa La La Half Marathon 10K & 5K Westminster CO
Sat Dec 7 Four Corners Quad Keyah Marathon Half Marathon & 5k Four Corners Monument CO
Sun Dec 8 Rock Canyon Half Marathon Pueblo CO

January 2025

February 2025

Sun Feb 9 Super Half Marathon and Game Day 5k Colorado Springs CO
Sun Feb 16 Stories Ultra 6H Half Marathon & 10k Colorado Springs CO
Sat Feb 22 All-Out Mardi Crawl Half Marathon 10K & 5K Arvada CO
TBD Feb Ralston Creek Half Marathon & 5k Arvada CO

March 2025

April 2025

May 2025

June 2024

Fall Color Dallas Divide in Colorado; home to Colorado half marathons

Frequently Asked Questions About Colorado Half Marathons

What are the most popular Colorado half marathons?

The four most popular Colorado half marathons are the Denver Colfax Half Marathon, the REVEL Rockies Half Marathon, the Horsetooth Half Marathon, and Boulderthon.

What’s the best half marathons in Colorado for beginners in 2024?

We have three picks for the best beginner Colorado half marathons. The first is the Slacker Half Marathon for it’s fun fast downhill course. Secondly, Boulderthon, for it’s scenic course, huge crowds, and amazing production quality. And finally, the Denver Colfax Half Marathon for it’s notable and exciting course and race experience.

What’s the best month to run a half marathon in Colorado?

September and October are the most popular months to run Colorado half marathons.

What are the most popular cities to run Colorado half marathons?

Colorado Springs, Boulder, and Denver are the most popular cities to run a Colorado half marathon in.