| Language | Population | Bloc | Family | Cluster | Band | |
|---|---|---|---|---|---|---|
| ● Kap | 4,620 | Austronesian | Oceanic | North New Guinea | Siau | |
| ● Malol | 4,310 | Austronesian | Oceanic | North New Guinea | Siau | |
| ● Ulau-Suain | 3,740 | Austronesian | Oceanic | North New Guinea | Siau | |
| ● Arop-Sissano | 1,820 | Austronesian | Oceanic | North New Guinea | Siau | |
| ● Tumleo | 1,050 | Austronesian | Oceanic | North New Guinea | Siau | |
| ● Sera | 670 | Austronesian | Oceanic | North New Guinea | Siau | |
| ● Sissano | 430 | Austronesian | Oceanic | North New Guinea | Siau |