| 15571 | 27 Sep 25 | 2025 Cedar Mountain Rally 5k/10k | 10K/5K | Orange, VA |
| 15572 | 04 Oct 25 | 2025 Cedar Creek Park Fall Duathlon | triathlon | Seaford, NY |
| 15573 | 17 Aug 25 | 2025 Cazenovia Triathlon | triathlon | Cazenovia, NY |
| 15574 | 04 Oct 25 | 2025 Castle Creek Triathlon | triathlon | Morristown, AZ |
| 15575 | 09 Aug 25 | 2025 Cassadaga Kids Triathlon | triathlon | Cassadaga, NY |
| 15576 | 21 Sep 25 | 2025 Carlyle Lake Triathlon | triathlon | Carlyle Township, IL |
| 15577 | 20 Sep 25 | 2025 Carderock Charge 5k/10k/Half | 10K/13.1/5K | Potomac, MD |
| 15578 | 28 Sep 25 | 2025 Captiva Island Triathlon | triathlon | Captiva Island, FL |
| 15579 | 07 Sep 25 | 2025 Captain Kids Triathlon . . | triathlon | Galveston, TX |
| 15580 | 23 Aug 25 | 2025 Capital City Kids Triathlon | triathlon | Lansing, MI |
| 15581 | 20 Dec 25 | 2025 Candy Cane 5k/10k | 10K/5K | Alexandria, VA |
| 15582 | 20 Jul 25 | 2025 Cal Tri Williamsburg | triathlon | Williamsburg, VA |
| 15583 | 17 Aug 25 | 2025 Cal Tri Walnut Creek | triathlon | North Garden, VA |
| 15584 | 02 Nov 25 | 2025 Cal Tri Newport Dunes . . | triathlon | Newport Beach, CA |
| 15585 | 19 Oct 25 | 2025 Cal Tri LA | triathlon | Playa del Rey, CA |