Sorted alphabetically by last name · 2711 fighters
| Name | Nickname | |
|---|---|---|
| NP | Norman Parke | "Stormin'" |
| NR | Nursulton Ruziboev | "Black" |
| NA | Nurullo Aliev | "Tajik Eagle" |
| NT | Nyamjargal Tumendemberel | "Art of Knockout" |
| OE | Oban Elliott | "The Welsh Gangster" |
| OO | Ode Osbourne | "The Jamaican Sensation" |
| OT | Oleg Taktarov | "The Russian Bear" |
| OT | Oli Thompson | |
| OE | Oliver Enkamp | |
| OA | Olivier Aubin-Mercier | "The Canadian Gangster" |