- Ōkawaotsu
- Ōtomachi-amaya
- Ōtomachi-ashinomaki
- Ōtomachi-kamimiyori
- Obara
- Ōdaki
- Ōhira
- Ōbori
- Ochiai
- Ōhanachi
- Onoda
- Oragahama
- Ōyauchi
- Okada
- Odaira
- Odaka
- Okudaira
- Ogawamachi-shioda
- Ogawamachi-takahagi
- Ogawamachi-uwadaira
- Onahama
- Ōtsu
- Owagamachi-shimo’ogawa
- Ōtaira
- Oikawa
- Ōhara
- Ōkubo
- Ōsemachi-kōzu
- Ōsemachi-tadano
- Ōtsukimachi