O
- (Yenegoa) Okutukutu
- (Brass) Okunbiri
- (Sagbama) Okumbiri
- (Southern Ijaw) Okubie
- (Southern Ijaw) Opotuwari
- (Southern Ijaw) Okpotububo
- (Southern Ijaw) Okpotububo
- (Brass) Okpoma
- (Ogbia) Okpokiri
- (Ogbia) Okpiniama
- (Nembe) Okparantaba
- (Brass) Okoroba
- (Nembe) Okokokiri
- (Ogbia) Okodogu
- (Nembe) Okipirri
- (Brass) Okinbiribalo
- (Southern Ijaw) Oki Gbone
- (Yenegoa) Ogu
- (Southern Ijaw) Ogoubiri
- (Southern Ijaw) Ogilagbene
- (Sagbama) Ogbonogbene
- (Ogbia) Ogbomama
- (Southern Ijaw) Ogboinbiri
- (Sagbama) Ofoni
- (Sagbama) Odobor
- (Ogbia) Odobio
- (Brass) Odioma
- (Ogbia) Ogidiama
- (Southern Ijaw) Ogbogoro
- (Brass) Obioku