Youngest champions
Youngest fighters to win an undisputed UFC title, by age on the day.
Reigns are derived from championship bouts. When a belt was vacated or stripped outside a title fight, the reign is shown ending at the next title fight in that division, so a few run long; a title awarded without a fight (José Aldo's in 2010, for one) starts at the champion's first UFC title fight.
109 fighters.
| # | Fighter | Age | Division | Won | Ended |
|---|---|---|---|---|---|
| 101 | Murilo Bustamante | 35 years, 165 days | Middleweight | Jan 11, 2002 | Feb 5, 2005 |
| 102 | Maurice Smith | 35 years, 226 days | Heavyweight | Jul 27, 1997 | Dec 21, 1997 |
| 103 | Belal Muhammad | 36 years, 18 days | Welterweight | Jul 27, 2024 | May 10, 2025 |
| 104 | Daniel Cormier | 36 years, 64 days | Light Heavyweight | May 23, 2015 | Dec 29, 2018 |
| 105 | Michael Bisping | 37 years, 97 days | Middleweight | Jun 4, 2016 | Nov 4, 2017 |
| 106 | Justin Gaethje | 37 years, 212 days | Lightweight | Jun 14, 2026 | Champion |
| 107 | Jan Blachowicz | 37 years, 215 days | Light Heavyweight | Sep 26, 2020 | Oct 30, 2021 |
| 108 | Fabricio Werdum | 37 years, 318 days | Heavyweight | Jun 13, 2015 | May 14, 2016 |
| 109 | Glover Teixeira | 42 years, 2 days | Light Heavyweight | Oct 30, 2021 | Jun 11, 2022 |