About Us

Now in its 18th year, the Colfax Marathon Partnership is a nonprofit 501c3 with the mission of producing the premier marathon weekend in the Mountain West Region, committed to community, philanthropy, and fun.  Originally created by the cities of Denver, Lakewood, and Aurora to recognize Colfax Avenue, the longest main street in America; it’s Denver’s only marathon.  The race has grown to be a nationally recognized event featuring unique courses incorporating the iconic landmarks of the Mile-High City.  In addition to Marathon Weekend, there are other events in the year such as the annual Colorado Running Hall of Fame evening with new inductees and high school athlete recognition.  And, there are other races during the year – which include Runner’s Reunion, Mile High Women’s 5K, and Welcome Back Denver 5K.

Major Sporting Event

The Colfax Marathon weekend is the largest marathon weekend in the Rocky Mountains, with 21,000 runners in 2023.  Races include a marathon, half marathon, urban 10 miler, and a 5K.  In addition, the marathon relay has over 1,330 teams in Corporate, Government or Open divisions and is the second largest Marathon Relay in the US.

As Denver’s largest running event, the Colfax Marathon includes seven races over two days and a two-day Health & Fitness Expo.  Runner’s World has selected Colfax Marathon in its top 10 lists in multiple years!

Each year, the Colfax Marathon is held the third Sunday in May, with the Expo and races making a fun three-day weekend.


Each year, the Colfax Marathon partners with more than 200 Nonprofits, who have collectively raised over $2,500,000 over the last 5 years through the efforts of Colfax runners.  The marathon’s Charity Partners Program is the 2nd largest in the U.S. with New York City Marathon being the largest.  An open door policy exists for all 501c3’s – welcoming small to large charities with a large variety of causes.  Click Here to learn more about charities raising money.


The Colfax Marathon each year donates more than $100,000 to its partners.  Corporate, Government, and Open Relay teams compete in their industries to win up to $2,500 each, which they designate a nonprofit partner to receive.  There are 80 awards in total, adding up to $100,000 each year.

Over the last 5 years, the 200+ charities have raised over $2.5 million through runners raising money for their causes.  This is in addition to the $100,000 that the Colfax Marathon donates annually.


In 2018, the Corporate and Government Relay Divisions included 4,500 runners on 900 teams, competing in a variety of industry categories.  Divisions include Accounting, Construction, Consumer Products/Services, Finance, Healthcare, Energy, High Tech, Legal, Professional Products/Services, Hospitality, Public School Teachers, and Government Employees.  Bragging rights and money for charity ($100,000 prize pool) are up for grabs! Click Here for Corporate Relay and Click Here for Government Relay information.



Companies across Colorado partner with the Colfax Marathon in a variety of ways – sponsoring, competing in the Corporate Relay, or bringing runners to participate in the individual race distances.  Many companies have one or more charities they focus on when participating in Colfax, to raise awareness or funds.  Click Here to get your company involved.


The Colfax Marathon Partnership Board of Directors is comprised of government and corporate executives.

The Colfax Marathon Staff are seasoned executives and running enthusiasts, working together to produce an event for runners by runners.

View Board of Directors and Staff


For more information, email info@runcolfax.org