| 15541 | 20 Jul 25 | 2025 Columbia Association Kids Triathlon | triathlon | Columbia, MD |
| 15542 | 05 Oct 25 | 2025 Cohutta Triathlon | triathlon | Crandall, GA |
| 15543 | 02 Aug 25 | 2025 Cohasset Kids Triathlon | triathlon | Cohasset, MA |
| 15544 | 03 Aug 25 | 2025 Coca Strong 5k/10k Hope in Every Step | 10K/5K | Valley Cottage, NY |
| 15545 | 19 Jul 25 | 2025 Clear Lake Sprint and Olympic Triathlons | triathlon | Fremont, IN |
| 15546 | 17 Aug 25 | 2025 Clayton Kids Triathlon | triathlon | Clayton, MO |
| 15547 | 10 Aug 25 | 2025 Classic City Sprint, Duathlon and Aquabike | triathlon | Athens, GA |
| 15548 | 10 Aug 25 | 2025 City of Edinburg Triathlon | triathlon | Edinburg, TX |
| 15549 | 01 Sep 25 | 2025 Cincinnati Aruna Run | 10K/1M/5K | Cincinnati, OH |
| 15550 | 06 Sep 25 | 2025 Chroma Team Racing Championship . . | triathlon | Nashville, TN |
| 15551 | 26 Jul 25 | 2025 Christmas in July 5k/Half | 13.1/5K | Washington, DC |
| 15552 | 24 Dec 25 | 2025 Christmas Eve 5k/10k | 10K/5K | Washington, DC |
| 15553 | 27 Jul 25 | 2025 Chisago Lakes Triathlon - Sunday | triathlon | Chisago, MN |
| 15554 | 26 Jul 25 | 2025 Chisago Lakes Kids Triathlon - Saturday | triathlon | Chisago, MN |
| 15555 | 01 Aug 25 | 2025 Chile Harvest YOUTH Triathlon - FRIDAY | triathlon | Socorro, NM |