| Fighter | Record | Last Bout |
|---|---|---|
| Jules Bruchez | 1-2-0 | 2008-12-13 |
| Junie Browning | 5-6-0 | 2009-04-01 |
| Justin Buchholz | 15-10-0 | 2010-02-06 |
| KB Bhullar | 8-2-0 | 2021-05-01 |
| Keith Berish | 5-1-0 (1 NC) | 2016-12-09 |
| Kevin Burns | 12-7-0 | 2009-12-12 |
| Kyle Bochniak | 8-5-0 | 2019-10-18 |
| Kyle Bradley | 19-12-0 (1 NC) | 2010-01-11 |
| Lance Benoist | 7-2-0 | 2014-06-07 |
| Luke Barnatt | 13-4-0 | 2015-05-16 |
| Mads Burnell | 9-3-0 | 2018-05-27 |
| Magomed Bibulatov | 14-2-0 | 2019-02-02 |
| Mandy Bohm | 8-2-0 (1 NC) | 2023-05-13 |
| Manny Bermudez | 14-2-0 | 2019-10-18 |
| Mara Romero Borella | 12-9-0 (2 NC) | 2020-09-19 |
| Marcin Bandel | 15-7-0 | 2015-04-11 |
| Marco Beltran | 8-6-0 | 2017-10-07 |
| Marcus Bossett | 1-3-0 | 1996-12-07 |
| Marcus Brimage | 7-7-0 | 2015-07-18 |
| Mark Bocek | 12-5-0 | 2014-04-16 |
| Martin Bravo | 11-3-0 | 2019-09-21 |
| Matt Bessette | 22-9-0 (1 NC) | 2018-07-06 |
| Matt Brown | 26-19-0 | 2023-05-13 |
| Matt Van Buren | 7-6-0 | 2015-01-18 |
| Maximo Blanco | 12-8-1 (1 NC) | 2016-09-17 |
| Mehdi Baghdad | 11-5-0 | 2016-07-07 |
| Melton Bowen | 0-1-0 | 1994-12-16 |
| Michael Bisping | 30-9-0 | 2017-11-25 |
| Michel Batista | 4-1-0 (1 NC) | 2018-11-30 |
| Miguel Baeza | 10-4-0 | 2024-06-08 |
| Mike Breeden | 11-6-0 | 2023-10-21 |
| Mike Brown | 26-9-0 | 2013-08-17 |
| Mikey Burnett | 5-2-0 | 1999-01-08 |
| Mirsad Bektic | 13-4-0 | 2020-09-19 |
| Murilo Bustamante | 15-8-1 | 2002-05-10 |
| Nah-Shon Burrell | 15-7-0 (1 NC) | 2013-05-25 |
| Niklas Backstrom | 11-3-0 (1 NC) | 2015-06-20 |
| Oluwale Bamgbose | 6-4-0 | 2017-12-16 |
| Pat Barry | 8-7-0 | 2013-12-06 |
| Paul Bradley | 23-8-0 (2 NC) | 2011-11-12 |
| Paul Buentello | 35-17-0 | 2010-03-21 |
| Peter Barrett | 11-5-0 | 2020-12-12 |
| Phil Baroni | 15-18-0 | 2011-01-01 |
| Poliana Botelho | 8-5-0 | 2022-06-04 |
| Ray Borg | 13-5-0 | 2020-05-13 |
| Renan Barao | 34-9-0 (1 NC) | 2019-11-16 |
| Rob Broughton | 16-7-1 | 2011-11-05 |
| Roger Bowling | 12-6-0 (1 NC) | 2013-12-14 |
| Rogerio Bontorin | 16-4-0 (2 NC) | 2022-01-15 |
| Roman Bogatov | 10-1-0 | 2020-07-11 |