Half-Marathon races in Colorado, United States — 2026 running calendar

May

02

Longmont Half & 5k (LM Half)

Longmont, Colorado, United States

$39.00 - $64.00

Running

Half-Marathon 5K

May

02

The Colorado Marathon

Fort Collins, Colorado, United States

Running

Marathon Half-Marathon 5K 10K

May

08

Run for Chocolate 5k/10k/13.1 Denver/Aurora

Centennial, Colorado, United States

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +8

May

29

SuperHeroes Run Denver/Aurora

Centennial, Colorado, United States

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +8

Jun

06

Colorado 13er (Half Marathon/10k/5k)

Louisville, Colorado, United States

$35.00 - $65.00

Running

Half-Marathon 10K 5K

Jun

06

The Steamboat Marathon

Steamboat Springs, Colorado, United States

$70.00 - $125.00

Running

Marathon Half-Marathon 10K

Jun

12

All-Out Summer Breeze

Arvada, Colorado, United States

$20.00 - $65.00

Running

Half-Marathon 10K 5K +2

Jun

19

Run Juneteenth Day 5K/10K/13.1 Denver/Aurora

Centennial, Colorado, United States

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +2

Jun

19

Red, White and Brew 5k, 10k & Half Marathon

Windsor, Colorado, United States

$18.00 - $68.00

Running

5K 10K Half-Marathon 1.6K +2

Jun

24

Race in the Clouds - Alma Dirt Festival

Alma, Colorado, United States

Free - $90.00

Running Mountain biking Duathlon Trail running

Weekend Camping FREE Kids Mountain Bike and Trail Run Ultra Marathon +7

Jun

26

Slacker Half Marathon-Relay-4-Mile Races

Georgetown, Colorado, United States

$35.00 - $90.00

Running

Half-Marathon 6.4K +3

Jul

10

All-Out Dog Days

Westminster, Colorado, United States

$20.00 - $65.00

Running

Half-Marathon 10K 5K +2