| Fighter | Record | Last Bout |
|---|---|---|
| Roman Salazar | 10-6-0 (1 NC) | 2015-08-08 |
| Ron Stallings | 14-8-0 (1 NC) | 2015-09-05 |
| Rory Singer | 11-9-0 | 2007-06-16 |
| Rosi Sexton | 13-5-0 | 2013-10-26 |
| Ryan Spann | 24-12-0 | 2026-09-05 |
| Sabah Homasi | 11-8-0 | 2018-01-20 |
| Sabina Mazo | 9-4-0 | 2022-03-12 |
| Saeed Hosseini | 0-1-0 | 1997-05-30 |
| Sage Northcutt | 11-2-0 | 2018-07-14 |
| Sai Wang | 20-6-1 | 2014-08-23 |
| Said Nurmagomedov | 18-5-0 | 2025-07-26 |
| Saidyokub Kakhramonov | 10-3-0 | 2022-12-17 |
| Saimon Oliveira | 18-7-0 | 2025-10-11 |
| Sako Chivitchian | 8-1-0 | 2010-12-04 |
| Salahdine Parnasse | 24-2-0 | 2026-09-05 |
| Salim Touahri | 10-4-0 | 2019-08-03 |
| Sam Adkins | 7-20-2 | 1996-09-20 |
| Sam Alvey | 33-18-1 (1 NC) | 2022-08-06 |
| Sam Fulton | 0-2-0 | 1997-07-27 |
| Sam Hoger | 10-4-0 | 2007-02-03 |
| Sam Hughes | 11-7-0 | 2026-03-14 |
| Sam Patterson | 15-3-1 | 2026-07-25 |
| Sam Sicilia | 15-8-0 | 2017-02-19 |
| Sam Stout | 20-12-1 | 2015-08-23 |
| Sammy Morgan | 18-12-0 | 2006-08-17 |
| Samy Schiavo | 10-6-0 | 2008-10-18 |
| Sanae Kikuta | 31-9-3 (1 NC) | 2000-04-14 |
| Sangwook Kim | 13-4-0 | 2026-01-31 |
| Santiago Luna | 8-1-0 | 2026-06-06 |
| Santiago Ponzinibbio | 31-10-0 | 2026-07-25 |
| Saparbeg Safarov | 9-3-0 | 2020-03-07 |
| Sara McMann | 13-6-0 | 2022-03-26 |
| Sarah Alpar | 9-6-0 | 2021-09-18 |
| Sarah Frota | 9-2-0 | 2019-07-27 |
| Sarah Kaufman | 18-4-0 (1 NC) | 2015-12-19 |
| Sarah Moras | 6-8-0 | 2021-01-16 |
| Sasha Palatnikov | 6-4-0 | 2021-08-21 |
| Satoshi Honma | 4-6-3 | 2000-04-14 |
| Saygid Izagakhmaev | 22-4-0 | 2026-07-25 |
| Scott Adams | 8-1-0 | 2000-03-10 |
| Scott Askham | 14-4-0 | 2017-03-18 |
| Scott Baker | 1-1-0 | 1994-03-11 |
| Scott Bessac | 4-6-0 | 1995-12-16 |
| Scott Ferrozzo | 4-2-0 | 1997-02-07 |
| Scott Fiedler | 0-1-0 | 1996-07-12 |
| Scott Holtzman | 14-6-0 | 2022-12-03 |
| Scott Jorgensen | 15-12-0 | 2015-11-21 |
| Scott Junk | 8-3-1 (1 NC) | 2007-09-22 |
| Scott Morris | 2-1-0 | 1994-03-11 |
| Scott Smith | 18-11-0 (1 NC) | 2007-06-16 |