O
- (Esan South-East) Oria
- (Uhunmwonde) Oria
- (Uhunmwonde) Orhua
- (Esan South-East) Orekhie
- (Ikpoba-Okha) Oregbeni
- (Ovia South-West) Ora
- (Ovia North-East) Ora
- (Owan West) Opuje
- (Esan Central) Opoji
- (Akoko-Edo) Onumu
- (Ovia North-East) Omi
- (Esan South-East) Omakwu
- (Ovia North-East) Olumoye
- (Ovia North-East) Oluku
- (Orhionmwon) Olote
- (Akoko-Edo) Oloma
- (Ikpoba-Okha) Ologbo
- (Orhionmwon) Ologbo
- (Ovia South-West) Olodiama
- (Esan North-East) Olihlin
- (Orhionmwon) Oligie
- (Ovia North-East) Old Iyekezie
- (Ovia South-West) Okwa
- (Ovia South-West) Okwa
- (Ovia South-West) Okuzuwa
- (Orhionmwon) Okuo
- (Ikpoba-Okha) Okuku
- (Etsako East) Okugbe
- (Ovia North-East) Okua
- (Oredo) Okua