O
- (Etsako East) Oku
- (Esan South-East) Okporporo
- (Ovia North-East) Okporoma
- (Ovia North-East) Okporakhor
- (Ovia South-West) Okponha
- (Owan East) Okpokhumi
- (Etsako East) Opepwe
- (Akoko-Edo) Okpe
- (Ovia South-West) Okoro
- (Ovia South-West) Okoro
- (Ikpoba-Okha) Okonaovi
- (Ovia North-East) Okomwere
- (Ovia South-West) Okomu
- (Ovia South-West) Okome
- (Ovia South-West) Okokpon
- (Ovia North-East) Okhuo
- (Ovia North-East) Okohohon
- (Orhionmwon) Okogbo
- (Oredo) Oko
- (Uhunmwonde) Okhuokho
- (Uhunmwonde) Okhuo
- (Ovia North-East) Okhunmwum
- (Esan South-East) Okhuessan
- (Uhunmwonde) Okhuepen
- (Uhunmwonde) Okhuaihe
- (Ovia South-West) Okha
- (Ikpoba-Okha) Okha
- (Uhunmwonde) Okeze
- (Ovia South-West) Okeyuyu
- (Uhunmwonde) Okemue