| 181 | 27 Mar 26 | 2026 CLASH Miami Triathlon - Sunday Events | triathlon | Homestead, FL |
| 182 | 20 Jun 26 | 2026 Clemson Triathlon | triathlon | Seneca, SC |
| 183 | 06 Jun 26 | 2026 Colorado Triathlon | triathlon | Boulder, CO |
| 184 | 12 Apr 26 | 2026 Columbia Gateway Duathlon | triathlon | Columbia, MD |
| 185 | 14 Jun 26 | 2026 Columbia River Half Iron | triathlon | Vantage, WA |
| 186 | 16 Feb 26 | 2026 Commander-in-Chief Chase 5k/10k | 10K/5K | Spotsylvania, VA |
| 187 | 13 Jun 26 | 2026 Cool Sommer Mornings Tri Series #1 | triathlon | Clermont, FL |
| 188 | 11 Jul 26 | 2026 Cool Sommer Mornings Triathlon Series #2 | triathlon | Clermont, FL |
| 189 | 15 Feb 26 | 2026 Coronado Valentine's Day 10K, 5K and 1 Mile Fun Run/Walk | 5K/10K | Coronado, CA |
| 190 | 26 Jul 26 | 2026 Crescent City Triathlon | triathlon | Crescent, CA |
| 191 | 14 Feb 26 | 2026 Crush Rush 5K | 5K | The Woodlands, TX |
| 192 | 07 Feb 26 | 2026 CTC Super Bowl Duathlon | triathlon | Clermont, FL |
| 193 | 28 Mar 26 | 2026 Culpeper Airport 5k | 5K | Culpeper, VA |
| 194 | 28 Mar 26 | 2026 Dare to Tri - Fort Gordon | triathlon | Fort Eisenhower, GA |
| 195 | 22 Feb 26 | 2026 Dash Around the Point 5k/10k | 10K/5K | Washington, DC |