West · CO

Running Races in Colorado

Colorado currently has 210 upcoming races with a confirmed date listed in RaceRove. Denver, Colorado Springs, Centennial and Littleton have the largest concentration of events.

By distance, that includes 143 5Ks, 63 10Ks, 38 half marathons and 10 marathons. Many events offer more than one distance, so a race can appear in more than one of those counts.

October (66), November (39) and September (33) are the busiest months on the calendar right now. Another 195 annual races are waiting for next year's date to be announced.

Upcoming, date confirmed
210
Active listings
405
Cities with races
106

Browse Colorado races by distance

Upcoming races in Colorado

The next 60 of 210 with a confirmed date, soonest first.

Dates come from each race's own listing. Always confirm on the organiser's site before you book travel.

Largest races in Colorado

By estimated field size across all distances at the event.

  • BolderBOULDER 10K
    Boulder, CO Usually held in May · date not confirmed
    10K ~50,000 runners
  • Denver Colfax Marathon
    Denver, CO Usually held in May · date not confirmed
    MarathonHalfUrban 10 MilerMarathon Relay +1 more ~25,000 runners
  • Boulder Marathon
    Boulder, CO Usually held in September · date not confirmed
    MarathonHalf ~15,000 runners
  • Boulderthon
    Boulder, CO Usually held in September · date not confirmed
    MarathonHalf Marathon10K5K +1 more ~15,000 runners
  • Mile High United Way Turkey Trot
    Denver, CO Usually held in November · date not confirmed
    4 Mile ~11,600 runners
  • Cherry Creek Sneak
    Denver, CO Usually held in April · date not confirmed
    10 Mile5 Mile5K ~8,000 runners
  • FORTitude 10K
    Fort Collins, CO Usually held in September · date not confirmed
    10Kplus shorter community options ~7,000 runners
  • Rock 'n' Roll Denver Marathon & Half Marathon
    Denver, CO Usually held in October · date not confirmed
    MarathonHalf10K5K ~7,000 runners

When races happen in Colorado

January
7 upcoming races
February
7 upcoming races
March
5 upcoming races
April
10 upcoming races
May
12 upcoming races
June
7 upcoming races
July
4 upcoming races
August
1 upcoming race
September
33 upcoming races
October
66 upcoming races
November
39 upcoming races
December
19 upcoming races

Colorado cities with the most races

Denver
19 upcoming races
Colorado Springs
19 upcoming races
Centennial
17 upcoming races
Littleton
12 upcoming races
Fort Collins
8 upcoming races
Westminster
8 upcoming races
Arvada
8 upcoming races
Estes Park
6 upcoming races

Annual events awaiting their next date

These races are held every year, but the next date isn't in the listing yet. The month shown is when each is usually held.

  • BolderBOULDER 10K
    Boulder, CO Usually held in May · date not confirmed
    10K ~50,000 runners
  • Denver Colfax Marathon
    Denver, CO Usually held in May · date not confirmed
    MarathonHalfUrban 10 MilerMarathon Relay +1 more ~25,000 runners
  • Boulder Marathon
    Boulder, CO Usually held in September · date not confirmed
    MarathonHalf ~15,000 runners
  • Boulderthon
    Boulder, CO Usually held in September · date not confirmed
    MarathonHalf Marathon10K5K +1 more ~15,000 runners
  • Mile High United Way Turkey Trot
    Denver, CO Usually held in November · date not confirmed
    4 Mile ~11,600 runners
  • Cherry Creek Sneak
    Denver, CO Usually held in April · date not confirmed
    10 Mile5 Mile5K ~8,000 runners
  • FORTitude 10K
    Fort Collins, CO Usually held in September · date not confirmed
    10Kplus shorter community options ~7,000 runners
  • Rock 'n' Roll Denver Marathon & Half Marathon
    Denver, CO Usually held in October · date not confirmed
    MarathonHalf10K5K ~7,000 runners
  • Highlands Ranch Turkey Day 5K
    Highlands Ranch, CO Usually held in November · date not confirmed
    5K ~3,000 runners
  • Pikes Peak Marathon & Ascent
    Manitou Springs, CO Usually held in September · next date not announced
    MarathonAscent (13.3 mi) ~2,600 runners
  • Colorado Springs Marathon
    Colorado Springs, CO Usually held in October · date not confirmed
    MarathonHalf ~2,500 runners
  • Leadville Trail Marathon
    Leadville, CO Usually held in June · date not confirmed
    Trail Marathon ~2,500 runners
  • Ugly Sweater 5K
    Denver, CO Usually held in December · date not confirmed
    5K ~2,500 runners
  • Horsetooth Half Marathon
    Fort Collins, CO Usually held in April · date not confirmed
    Half ~2,000 runners
  • HRCA Backcountry Wilderness Half Marathon
    Highlands Ranch, CO Usually held in November · date not confirmed
    Half10K5K ~2,000 runners
  • Steamboat Marathon
    Steamboat Springs, CO Usually held in June · date not confirmed
    MarathonHalf ~2,000 runners
  • Garden of the Gods 10 Mile
    Colorado Springs, CO Usually held in June · date not confirmed
    10 Mile10KTrail RunYouth Classic ~1,800 runners
  • Imogene Pass Run
    Ouray, CO Usually held in September · next date not announced
    17.1 Mile ~1,550 runners
  • Frosty's Frozen 5K, 10K & Half Marathon
    Littleton, CO Usually held in January · date not confirmed
    Half Marathon10K5K ~1,500 runners
  • Run the Rocks at Red Rocks
    Morrison, CO Usually held in October · date not confirmed
    10K5K ~1,500 runners
  • Super Half Marathon & Game Day 5K
    Colorado Springs, CO Usually held in February · date not confirmed
    Half Marathon5K ~1,500 runners
  • Thirsty 13 Half Marathon
    Durango, CO Usually held in August · next date not announced
    Half Marathon ~1,500 runners
  • Estes Park Marathon
    Estes Park, CO Usually held in June · date not confirmed
    MarathonHalf Marathon5 Mile ~1,000 runners
  • Old Man Winter Rally Run
    Lyons, CO Usually held in February · date not confirmed
    5K10KHalf Marathon ~1,000 runners
  • Snowman Stampede
    Littleton, CO Usually held in February · date not confirmed
    Half Marathon10K5K ~1,000 runners
  • Georgetown to Idaho Springs Half Marathon
    Idaho Springs, CO Usually held in August · date not confirmed
    Half ~800 runners
  • Leadville Trail 100 Run
    Leadville, CO Usually held in August · date not confirmed
    100 Miles ~800 runners
  • Slacker Half Marathon
    Georgetown, CO Usually held in June · date not confirmed
    Half4 MileRelay ~800 runners
  • Yeti Chase 5K & 10K
    Lakewood, CO Usually held in January · date not confirmed
    10K5K ~700 runners
  • Run the Rockies Trail Half Marathon
    Frisco, CO Usually held in August · date not confirmed
    5K10KHalf Marathon ~600 runners
  • Mt. Sneffels Half Marathon & 10K
    Ouray, CO Usually held in August · date not confirmed
    Half Marathon10K ~500 runners
  • Vail HillClimb
    Vail, CO Usually held in July · date not confirmed
    7.6 Mile uphill trail run ~500 runners
  • 10k at 10,000 Feet
    Steamboat Springs, CO Usually held in September · next date not announced
    8 Miles4 Miles
  • 31st El Grito 5k (2026)
    Denver, CO Usually held in September · next date not announced
    5K
  • 5K at the Fair
    Durango, CO Usually held in August · next date not announced
    5K
  • 6 Dot Dash
    Littleton, CO Usually held in September · next date not announced
    5K
  • 9/11 Heroes Run - Denver, Colorado
    Denver, CO Usually held in September · next date not announced
    5K1 Miles
  • All-Out Fall Fest
    Westminster, CO Usually held in September · next date not announced
    5K10K
  • All-Out Runapalooza
    Arvada, CO Usually held in August · next date not announced
    5K10K
  • American Heroes Run
    Longmont, CO Usually held in September · next date not announced
    100 Miler24 hrs6 hour open startVirtual - Any Distance

Races in nearby states

Guides from the RaceRove blog

Running Races in Colorado: common questions

How many races are there in Colorado?
RaceRove currently lists 210 upcoming races in Colorado with a confirmed date, plus 195 annual events whose next date hasn't been announced yet.
Which Colorado cities have the most races?
By upcoming events listed in RaceRove: Denver (19), Colorado Springs (19), Centennial (17), Littleton (12) and Fort Collins (8).
When is race season in Colorado?
Of the upcoming races listed, the busiest months are October (66), November (39) and September (33).
What is the biggest race in Colorado?
By estimated field size, the largest race listed in Colorado is the BolderBOULDER 10K, with about 50,000 runners across all of its distances.
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