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Half Marathons Found In Colorado in September
View all ↓Half Marathons in Colorado in September 2025
Find A Race is the US's favourite event listings site. Check out our list of September 2025 Half Marathons in Colorado below.
Race Calendar: Half Marathons Found In September
πBoosted
Rim to Rim Royal Gorge Races: 5K Road Run, Trail 8 Mile, Trail Half Marathon
Canon City, Colorado
20 Sep 25 - 07 Dec 25
Free - $186.50
πBoosted
Platte River Half-Marathon and Relay
Littleton, Colorado
13 Apr 25 - 12 Apr 26
$80.50 - $268.75
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Denver, CO Galloway Training Program
Denver, Colorado
20 Apr 24 - 05 Nov 25
$91.10 - $274.00
Fifty States Half Marathon Club General Membership
Colorado Springs, Colorado
02 May 24 - 02 Apr 34
$91.10
2025 Team CKF Running Series
Aspen, Colorado
22 Feb 25 - 30 Dec 25
Free
Fleet Feet Denver Fall Half-Marathon Twelve-Week Training Program
Littleton, Colorado
08 Jul 25 - 28 Sep 25
$155.00
Boulderthon Half Marathon Training Program
Boulder, Colorado
09 Jul 25 - 28 Sep 25
$150.00
Labor Day Half Marathon
Parker, Colorado
01 Sep 25
$37.64 - $83.00
Black Squirrel Half Marathon
Bellvue, Colorado
06 Sep 25
$107.00
All-Out Fall Fest
Westminster, Colorado
13 Sep 25
$32.80 - $69.90
Spooky Sprint - Colorado Springs
Colorado Springs, Colorado
13 Sep 25
$20.83 - $50.28
Trail Sisters Women's Half Marathon & 10k
Buena Vista, Colorado
13 Sep 25
$69.90 - $107.00
Fall Equinox
Fort Collins, Colorado
14 Sep 25 - 04 Oct 25
$65.65 - $140.03
Spooky Sprint - Denver
Littleton, Colorado
14 Sep 25
$23.98 - $53.28
Rim to Rim Royal Gorge Races: 5K Road Run, Trail 8 Mile, Trail Half Marathon
Canon City, Colorado
20 Sep 25 - 07 Dec 25
Free - $186.50
Autumn Run
Buena Vista, Colorado
20 Sep 25
$33.53 - $92.24
13th Annual Superhero Event
Greeley, Colorado
20 Sep 25 - 28 Sep 25
Free - $43.40
Red Feather Trail Jamboree
Red Feather Lakes, Colorado
26 Sep 25 - 28 Sep 25
$107.00 - $316.00
Pioneer Prairie Dog Half, 10k & 5k
Westminster, Colorado
27 Sep 25
Free - $80.00
WILD Wahatoya Runs
La Veta, Huerfano
27 Sep 25
$50.00 - $100.00
Prairie Dog Run Series
Louisville, Colorado
26 Jan 25 - 27 Sep 25
$900.00
Platte River Half-Marathon and Relay
Littleton, Colorado
13 Apr 25 - 12 Apr 26
$80.50 - $268.75
The Colorado Marathon
Fort Collins, Colorado
04 May 25 - 03 May 26
$32.80 - $379.00
Showing 1-21 of 21 results