Colorado Half Marathons by Date • By City
Browse all 2020-2021 Colorado half marathons by month below. For each race, you’ll find course maps, elevation profiles, runner reviews, and how to sign up.
When you view a race, you’ll also find contact info if you’re having problems with your registration or need to contact the race directors.
January 2021
| Sat Jan 9 | All-Out Polar Prowl Half Marathon 10K & 5K | Arvada CO |
| Sun Jan 17 | Prairie Dog Half Marathon 10K & 5K | Louisville CO |
February 2021
| Sat Feb 6 | All-Out Mardi Crawl Half Marathon 10K & 5K | Lakewood CO |
| Sun Feb 7 | Super Half Marathon & 5K | Colorado Springs CO |
March 2021
| Sun Mar 7 | That Dam Run Half Marathon 10K & 5K | Greenwood Village CO |
| Tue Mar 9 | Dust Bowl Series Marathon Half Marathon 10K & 5K – Day 5 | Lamar CO |
| Sun Mar 21 | All-Out Spring Fever Half Marathon 10K & 5K | Golden CO |
| Sun Mar 21 | Spring Equinox Half Marathon | Fort Collins CO |
April 2020
| Sat Apr 4 | Runs with Scissors Marathon Half Marathon & 50K | Brighton CO |
| Sat Apr 4 | Three Creeks Half Marathon | Denver CO |
| Sun Apr 5 | Platte River Half Marathon & Relay | Littleton CO |
| Sat Apr 11 | Hoppin' Half Marathon 10-Mile 10K & 5K | Denver CO |
| Sun Apr 12 | Prairie Dog Half Marathon & 10K | Arvada CO |
| Sat Apr 18 | All-Out Beat the Heat Marathon Half Marathon 10K & 5K | Westminster CO |
| Sun Apr 19 | Desert RATS Trail Running Festival | Fruita CO |
| Sun Apr 19 | Horsetooth Half Marathon | Fort Collins CO |
| Sat Apr 25 | Westminster Trail Half Marathon 10K & 5K | Broomfield CO |
May 2020
| Sun May 3 | Colorado Marathon Half Marathon 10K & 5K | Fort Collins CO |
| Sat May 9 | Carbon Valley Half Marathon | Firestone CO |
| Sun May 10 | Rabbit Valley Half Marathon | Fruita CO |
| Sun May 17 | Colfax Marathon Half Marathon Urban 10-Miler & Relay | Denver CO |
June 2020
| Sat Jun 20 | Barr Lake Half Marathon & 15K | Brighton CO |
| Sat Jun 27 | All-Out Summer Breeze Half Marathon 10K 5K & 1-Mile | Arvada CO |
July 2020
| Sat Jul 18 | All-Out Dog Days Half Marathon 10K & 5K | Westminster CO |
| Sun Jul 19 | Sunlight Showdown Half Marathon | Glenwood Springs CO |
August 2020
| Sat Aug 1 | Rocky Mountain Half Marathon | Estes Park CO |
| Sat Aug 1 | South Park Trail Marathon & Half Marathon | Fairplay CO |
| Sat Aug 1 | Winter Park Half Marathon & 5K | Winter Park CO |
| Sat Aug 8 | Run the Rockies Trail Half Marathon & 10K | Frisco CO |
| Sun Aug 16 | Beaver Creek Half Marathon 10K & 5K | Avon CO |
| Sat Aug 22 | All-Out Runapalooza Half Marathon 10K & 5K | Arvada CO |
| Sat Aug 29 | Dynafit Half Marathon & 5K | Vail CO |
| Sat Aug 29 | Thirsty 13 Half Marathon | Durango CO |
September 2020
| Sun Sep 6 | Breck Crest Mountain Marathon Half Marathon & 10K | Breckenridge CO |
| Mon Sep 7 | Labor Day Half Marathon | Parker CO |
| Sat Sep 12 | American Heroes Run Marathon Half Marathon Ultra & 5K | Longmont CO |
| Sat Sep 12 | Black Squirrel Half Marathon | Fort Collins CO |
| Sat Sep 12 | Mountain Ridge Half Marathon & 10K | Highlands Ranch CO |
| Sat Sep 19 | All-Out Fallfest Marathon Half Marathon 10K & 5K | Westminster CO |
| Sat Sep 19 | Camp 4 Coffee Cart to Cart Trail Race | Crested Butte CO |
| Sat Sep 19 | Mountain Rats Marathon Half Marathon & 50K | Eagle CO |
| Sat Sep 19 | Snow Mountain Ranch Trail Running Festival | Granby CO |
October 2020
| Sat Oct 3 | Castle Rock Trail Festival | Castle Rock CO |
| Sat Oct 3 | Mine Shaft Half Marathon & Tommyknocker Ultras | Golden CO |
| Sat Oct 3 | Spanish Peaks Half Marathon & Fun Run | La Veta CO |
| Sun Oct 4 | Long View Marathon & Half Marathon | Fort Collins CO |
| Sun Oct 11 | Boulderthon Marathon & Half Marathon | Boulder CO |
| Sun Oct 11 | Breckenridge Brewery Half Marathon | Littleton CO |
| Sun Oct 11 | Run Through Time Marathon Half Marathon & Fun Run | Salida CO |
| Sun Oct 11 | Windsor Half Marathon & Heavy 10K | Windsor CO |
| Sun Oct 25 | All-Out Kooky Spooky Half Marathon 10K & 5K | Golden CO |
November 2020
| Sun Nov 1 | Colorado 13er Half Marathon 10K & 5K | Louisville CO |
| Sat Nov 7 | Backcountry Wilderness Half Marathon | Highlands Ranch CO |
| Mon Nov 9 | Southwest Series Marathon Half Marathon 10K & 5K – Day 2 | Durango CO |
December 2020
| Sat Dec 5 | All-Out Fa La La Half Marathon 10K & 5K | Westminster CO |
| Sun Dec 6 | Rock Canyon Half Marathon | Pueblo CO |
