| 3706 | 02 Aug 26 | Murabella Kids Triathlon | youth triathlon | Saint Augustine, FL |
| 3707 | 17 May 26 | Muncie Sprint and Olympic Triathlon #1 | Olympic/Sprint Triathlon | Selma, IN |
| 3708 | 18 Apr 26 | Mullet Man Triathlon | Sprint Triathlon | Perdido Key, FL |
| 3709 | 30 May 26 | Muleshoe Off-Road X-TRI and DU | offroad duathlon/offroad triathlon | Austin, TX |
| 3710 | 02 May 26 | Mulberry Stampede 5K | 5K | North Wilkesboro, NC |
| 3711 | 27 Jun 26 | Mukwonago YMCA Family Mud Run | 2M | Mukwonago, WI |
| 3712 | 11 Jul 26 | Mujeres on the Run | 5K | Chicago, IL |
| 3713 | 18 Jul 26 | Muir Woods Mountain Challenge | 10K/13.1M/30K | Stinson Beach, CA |
| 3714 | 27 Sep 26 | Mueller's Orchard Cider Run 5K - Sun. September 27th @ Mueller's Orchard (Linden, MI.) | 5K | Linden, MI |
| 3715 | 25 Apr 26 | MudHen Brewing Co. IPA 5K & Beer Mile | 5K | Wildwood, NJ |
| 3716 | 02 May 26 | Muddy River Half Marathon | 13.1M | Cape Girardeau, MO |
| 3717 | 19 Jul 26 | Muddy Princess - Virginia Beach, VA | 5K | Chesapeake, VA |
| 3718 | 13 Sep 26 | Muddy Princess - South Carolina | 5K | Gaston, SC |
| 3719 | 23 Aug 26 | Muddy Princess - Raleigh, NC | 5K | Raleigh, NC |
| 3720 | 14 Jun 26 | Muddy Princess - Pittsburgh, PA | 5K | Butler, PA |