Sorted alphabetically by last name · 2780 fighters
| Name | Nickname | |
|---|---|---|
| TG | Tyson Griffin | |
| TN | Tyson Nam | |
| TP | Tyson Pedro | |
| UG | Ulysses Gomez | "Useless" |
| UN | Umar Nurmagomedov | |
| US | Uran Satybaldiev | "Gorilla" |
| UH | Uriah Hall | "Prime Time" |
| UF | Urijah Faber |
| "The California Kid" |
| UM | Uros Medic | "The Doctor" |
| VR | Vagner Rocha | "Ceara" |