| 196 | 31 May 25 | 2025 Big Horn Challenge Triathlon | triathlon | Worland, WY |
| 197 | 27 Sep 25 | 2025 Big Hurt Multisport Adventure | triathlon | Port Angeles, WA |
| 198 | 12 Jul 25 | 2025 Big Shark New Town Triathlon - Saturday Kid's Triathlon | triathlon | St. Charles, MO |
| 199 | 13 Jul 25 | 2025 Big Shark New Town Triathlon - Sunday | triathlon | St. Charles, MO |
| 200 | 22 Jun 25 | 2025 Big Sky State Games Run Paddle Run | triathlon | Billings, MT |
| 201 | 28 Jun 25 | 2025 Birchwood Lakes Triathlon | triathlon | Medford, NJ |
| 202 | 21 Jun 25 | 2025 BisMan Triathlon | triathlon | Bismarck, ND |
| 203 | 14 Jun 25 | 2025 Black Butte Triathlon | triathlon | Corning, CA |
| 204 | 27 Sep 25 | 2025 Black Canyon Triathlon | triathlon | Montrose, CO |
| 205 | 28 Jun 25 | 2025 Black Diamond Triathlon | triathlon | Enumclaw, WA |
| 206 | 28 Nov 25 | 2025 Black Friday 5k/10k | 10K/5K | Herndon, VA |
| 207 | 21 Jun 25 | 2025 Blackfoot Kicker Triathlon | triathlon | Blackfoot, ID |
| 208 | 06 Sep 25 | 2025 Blackhawk YMCA Triathlon | triathlon | Waterloo, IA |
| 209 | 01 Sep 25 | 2025 Blackland Triathlon & Youth Triathlon (LABOR DAY) | triathlon | Plano, TX |
| 210 | 06 Sep 25 | 2025 Blake's Tinman Triathlon | triathlon | Reedsburg, WI |