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

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

Centennial, Colorado, United States

12 Sep, 2026 (Sat)

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +2

Beulah Challenge and OverIt Series

Beulah, Colorado, United States

19 Sep, 2026 (Sat)

$20.00 - $180.00

Running

Half-Marathon 10K 5K +2

All-Out Fall Fest

Westminster, Colorado, United States

19 Sep, 2026 (Sat)

$25.00 - $70.00

Running

Half-Marathon 10K 5K +2

Autumn Run

Buena Vista, Colorado, United States

19 Sep, 2026 (Sat)

Free - $90.00

Running

Half-Marathon 10K 5K 1K

Fall Equinox

Fort Collins, Colorado, United States

20 Sep, 2026 (Sun) – 03 Oct, 2026

$75.00 - $150.00

Running

Half-Marathon 8K

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

Centennial, Colorado, United States

26 Sep, 2026 (Sat)

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +2

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

Boulder, Colorado, United States

27 Sep, 2026 (Sun)

$40.00 - $500.00

Running

Half-Marathon 5K 10K

Colorado Springs Marathon, Half, 5K, and Kids K

Colorado Springs, Colorado, United States

03 Oct, 2026 (Sat)

Free - $110.00

Running

Marathon Half-Marathon 5K 1K +11

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

Canon City, Colorado, United States

03 Oct, 2026 (Sat)

$40.00 - $80.00

Running

5K 12.9K Half-Marathon 10K +2

Spooky Sprint - Denver

Littleton, Colorado, United States

03 Oct, 2026 (Sat)

$25.00 - $61.00

Running

1.6K 5K 10K Half-Marathon

Windsor Marathon, Half Marathon, 10k, 5k & 1 Mile Run

Windsor, Colorado, United States

04 Oct, 2026 (Sun)

$20.00 - $115.00

Running

Marathon Half-Marathon 10K 5K +1

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

Centennial, Colorado, United States

10 Oct, 2026 (Sat) – 28 Nov, 2026

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +8