Half Marathons in Colorado — 2026

There are 74 half marathons in Colorado scheduled for 2026. The next is the Barr Trail Mountain Race in Manitou Springs on July 19. Colorado half marathons run primarily July through February.

Summer Splash Prairie Dog Half, 10k, & 5k

Sat, Jul 18 · Castle Rock, CO Castle Rock

5k10kHalf Marathon

From $25 Open Closing Soon

Register →

Barr Trail Mountain Race

Sun, Jul 19 · Manitou Springs, CO Manitou Springs

BTMRAid Station Challenge Sponsor

From $75 Open Closing Soon 16 spots left

Register →

Run for Donuts 5K/10K/13.1 DENVER/AURORA

Sat, Jul 25 · Centennial, CO Centennial

Family 1 Mile Fun Run5K RegistrationVirtual Run Registration +3

From $30 Open Closing Soon

Register →

Run for Coffee Lovers 5K/10K/13.1 DENVER/AURORA

Sat, Jul 25 · Centennial, CO Centennial

Family Fun Run 1 Mile5K RegistrationVirtual Run Registration (5K/10K/13.1) +3

From $30 Open Closing Soon

Register →

Christmas 5K/10K/Half Marathon in July Meet Up - Denver

Sat, Jul 25 · Littleton, CO Littleton

5K10KHalf Marathon

From $35 Open Closing Soon

Register →

Popsicle 5K/10K/Half - Colorado Springs

Sat, Aug 1 · Colorado Springs, CO Colorado Springs

5KVirtual 5K5K-No Shirt +6

From $25 Open Closing Soon

Register →

Choice City Running Festival

Fri, Aug 7 · Fort Collins, CO Fort Collins

Jane Welzel Mountain Avenue MileHuman Race 5kHuman Race 10k +4

From $20 Open Closing Soon

Register →

All-Out Runapalooza

Sat, Aug 8 · Arvada, CO Arvada

VIRTUAL 5K5KVIRTUAL 10K +3

From $20 Open Closing Soon

Register →

Leadville Boomdays International Pack Burro Race

Sun, Aug 9 · Leadville, CO Leadville

SHORT COURSE: Leadville Boomdays International Pack Burro RaceLONG COURSE: Leadville Boomdays International Pack Burro Race

From $65 Open

Register →

Bagel Run 5K/10K/13.1 DENVER/AURORA

Sat, Aug 15 · Centennial, CO Centennial

Family Fun Run 1 Mile5K RegistrationVirtual Run Registration (5K/10K/13.1) +3

From $30 Open

Register →

Run for PB& J 5K/10K/13.1 DENVER/AURORA

Sat, Aug 15 · Centennial, CO Centennial

Family 1 Mile Fun RunVirtual Run Registration5K Registration +3

From $30 Open

Register →

Erie Half & 5k

Sun, Aug 16 · Erie, CO Erie

5kHalf Marathon

From $30 Open Closing Soon

Register →

Byers Peak Stampede Half Marathon & 5K Run

Sat, Aug 22 · Fraser, CO Fraser

5KHalf Marathon

From $45 Open

Register →

Pioneer Prairie Dog Half, 10k & 5k

Sun, Aug 23 · Westminster, CO Westminster

5k10kHalf Marathon

From $25 Open

Register →

Sloth Run 5K/10K/13.1 DENVER/AURORA

Sat, Aug 29 · Centennial, CO Centennial

Family 1 Mile Fun Run5K/10K/13.1 Eco-Registration (No Shirt)Virtual Run Registration +3

From $30 Open

Register →

TBK Bank Thirsty 13 Half Marathon

Sat, Aug 29 · Durango, CO Durango

Race Plus BrewfestJust The Race -- No Brewfest Ticket

From $85 Open

Register →

Run for Breast Cancer 5K/10K/13.1 DENVER/AURORA

Sat, Aug 29 · Centennial, CO Centennial

Family Fun Run 1 Mile5K Registration5K/10K/13.1 Eco-Registration (No Shirt) +3

From $30 Open

Register →

RMRR Fall Marathon Training Series

Sun, Aug 30 · Thornton, CO Thornton

RMRR Fall Marathon Training Series #1 - 10 MileRMRR Fall Marathon Training - 3 race bundle Short (10m, 20k, 10m)RMRR Fall 2023 Marathon Training Series #1 - 20 Mile +1

From $20 Open

Register →

Labor Day Half Marathon

Mon, Sep 7 · Parker, CO Parker

5K10KVirtual Race +1

From $27 Open Closing Soon

Register →

Run for Mental Health 5K/10K/13.1 DENVER/AURORA

Sat, Sep 12 · Centennial, CO Centennial

Family Fun Run 1 Mile5K Registration5K/10K/13.1 Eco-Registration (No Shirt) +3

From $30 Open

Register →

National Chocolate Day: Run for Chocolates 5K/10K/13.1 DENVER/AURORA

Sat, Sep 12 · Centennial, CO Centennial

Family 1 Mile Fun Run5K RegistrationVirtual Run Registration +3

From $30 Open

Register →

Black Squirrel Half Marathon

Sat, Sep 12 · Bellvue, CO Bellvue

Black Squirrel Half Marathon

From $90 Open

Register →

Battle by the Brook

Sat, Sep 19 · Deckers, CO Deckers

Family RaceCompetitive Race

From $89 Open 75 spots left

Register →

All-Out Fall Fest

Sat, Sep 19 · Westminster, CO Westminster

VIRTUAL 5K5K10K +3

From $20 Open

Register →

Beulah Challenge and OverIt Series - ON PAUSE DUE TO THE ASPEN ACRES FIRE

Sat, Sep 19 · Beulah, CO Beulah

5K5K - Age 17 & Under10K - Age 17 & Under +3

From $20 Open Closing Soon

Register →

Pikes Peak Ascent

Sat, Sep 19 · Manitou Springs, CO Manitou Springs

Half Priced Award EntryAscent

From $87.5 Open

Register →

Fall Equinox

Sun, Sep 20 · Fort Collins, CO Fort Collins

5 MileVirtual 5 MileVirtual Half Marathon +1

From $50 Open Closing Soon

Register →

20th Annual Golden Gallop

Sun, Sep 20 · Golden, CO Golden

5K10K20K Challenge - ONLY 10K completed on race day, remaining 10K done virtually +2

From $25 Open

Register →

Oktoberfest Run 5K/10K/13.1 DENVER/AURORA

Sat, Sep 26 · Centennial, CO Centennial

Family 1 Mile Fun Run5K Registration5K/10K/13.1 Eco-Registration (No Shirt) +3

From $30 Open

Register →

Run for Donuts 5K/10K/13.1 DENVER/AURORA

Sat, Sep 26 · Centennial, CO Centennial

Family Fun Run 1 Mile5K RegistrationVirtual Run Registration (5K/10K/13.1) +3

From $30 Open

Register →

14er Fest 14K & 5K

Sun, Sep 27 · Buena Vista, CO Buena Vista

5K14K

From $35 Open

Register →

Running for Children's Rights to Both Parents - 9 of 50 Half Marathons in 50 States - Colorado

Sun, Sep 27 · Boulder, CO Boulder

5K (Virtual)10K (Virtual)1/2 Marathon (In-Person) +1

From $40 Open

Register →

RMRR Fall Marathon Training Series #3

Sun, Sep 27 · Thornton, CO Thornton

RMRR Fall Marathon Training Series #3 - 10 MileRMRR Fall Marathon Training Series #3 - 20 Mile

From $20 Open

Register →

Rim to Rim Royal Gorge Races: 5K Road Run, Trail 8 Mile, Trail Half Marathon

Sat, Oct 3 · Canon City, CO Canon City

VIRTUAL 5k Run/Walk5K Road Run8 Mile Trail Run +3

From $40 Open Closing Soon

Register →

Emerald Mountain Trail Run

Sat, Oct 3 · Steamboat Springs, CO Steamboat Springs

4 Mile12k

From $25.75 Open

Register →

Coffee Lovers Run 5K/10K/13.1 DENVER/AURORA

Sat, Oct 10 · Centennial, CO Centennial

Family Fun Run 1 Mile5K RegistrationVirtual Run Registration (5K/10K/13.1) +3

From $30 Open

Register →

Bagel Run 5K/10K/13.1 DENVER/AURORA

Sat, Oct 10 · Centennial, CO Centennial

Family 1 Mile Fun Run5K RegistrationVirtual Run Registration +3

From $30 Open

Register →

Westy Half & 5k

Sun, Oct 11 · Westminster, CO Westminster

5kHalf Marathon

From $30 Open

Register →

Mancos Cowboy Half Marathon, 5K, and Fun Run

Sat, Oct 24 · Mancos, CO Mancos

Mancos 5KMancos Cowboy Half Marathon

From $25 Open

Register →

Halloween Trick or Trot Run 5K/10K/13.1 DENVER/AURORA

Sat, Oct 31 · Centennial, CO Centennial

Family 1 Mile Fun Run5K RegistrationVirtual Run Registration +3

From $30 Open

Register →

PB&J Fuel Run 5K/10K/13.1 DENVER/AURORA

Sat, Oct 31 · Centennial, CO Centennial

Family Fun Run 1 Mile5K RegistrationVirtual Run Registration (5K/10K/13.1) +3

From $30 Open

Register →

RMRR November 5k/15k

Sun, Nov 1 · Denver, CO Denver

5k15k

From $10 Open

Register →

All-Out Kooky-Spooky

Sun, Nov 1 · Golden, CO Golden

VIRTUAL 5K5K10K +3

From $20 Open

Register →

Run for Mental Health 5K/10K/13.1 DENVER/AURORA

Sat, Nov 14 · Centennial, CO Centennial

Family 1 Mile Fun Run5K Registration5K/10K/13.1 Eco-Registration (No Shirt) +3

From $30 Open

Register →

Veterans Day Freedom Run 5K/10K/13.1 DENVER/AURORA

Sat, Nov 14 · Centennial, CO Centennial

Family Fun Run 1 Mile5K RegistrationVirtual Run Registration (5K/10K/13.1) +3

From $30 Open

Register →

TURKEY TREK (13.1, 10k, 5k & 2k)

Sat, Nov 21 · Arvada, CO Arvada

2k Turkey Toddle (un-timed)5k Turkey Trot10k Turkey Trek +1

From $26 Open Closing Soon

Register →

Thanksgiving Gobble Trot Run 5K/10K/13.1 DENVER/AURORA

Sat, Nov 28 · Centennial, CO Centennial

Family Fun Run 1 MileVirtual Run Registration (5K/10K/13.1)5K Registration +3

From $30 Open

Register →

Coffee Lovers Run 5K/10K/13.1 DENVER/AURORA

Sat, Nov 28 · Centennial, CO Centennial

Family 1 Mile Fun RunVirtual Run Registration5K Registration +3

From $30 Open

Register →

Chasing Santa 5k/Cycling Santa Toy Drive Presented by: Springs Law Group

Sat, Dec 5 · Colorado Springs, CO Colorado Springs

Toddlers Chasing SantaAdult Chasing Santa 5kChasing Santa 5k KIDS 15 yrs and under +5

From $0 Open

Register →

All-Out Fa La La

Sat, Dec 5 · Westminster, CO Westminster

VIRTUAL 5K5KVIRTUAL 10K +3

From $20 Open

Register →