Residents of Onondaga — Sub-district B, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 20 | oconnel | james | M | 55 | Roman Catholic | Irish | Ireland | No Occupation Listed | 135 |
| 21 | ohara | catharine | F | 16 | Anglican | Irish | Ontario | No Occupation Listed | 26 |
| 20 | ohara | james | M | 18 | Anglican | Irish | Ontario | No Occupation Listed | 26 |
| 17 | ohara | john | M | 57 | Anglican | Irish | Ontario | Farmers, general and nfs | 26 |
| 18 | ohara | margaret | F | 56 | Wesleyan Methodist | Irish | Ontario | No Occupation Listed | 26 |
| 19 | ohara | maria | F | 20 | Anglican | Irish | Ontario | No Occupation Listed | 26 |
| 22 | ohara | samilda | F | 14 | Anglican | Irish | Ontario | No Occupation Listed | 26 |
| 23 | ohara | william | M | 1 | Anglican | Irish | Ontario | No Occupation Listed | 26 |
| 13 | oliver | adam | M | 40 | Anglican | Scottish | Scotland | "Farmer and fisherman" | 47 |
| 2 | oliver | agnes | F | 61 | Presbyterian Episcopal | Scottish | Scotland | No Occupation Listed | 126 |
| 25 | oliver | annie | F | 20 | Presbyterian Episcopal | Scottish | Ontario | No Occupation Listed | 126 |
| 23 | oliver | douglass | M | 25 | Presbyterian Episcopal | Scottish | Ontario | Teachers (music) | 126 |
| 22 | oliver | duncan | M | 27 | Presbyterian Episcopal | Scottish | Ontario | Farmers, general and nfs | 126 |
| 24 | oliver | ellen | F | 23 | Presbyterian Episcopal | Scottish | Ontario | No Occupation Listed | 126 |
| 10 | oliver | george | M | 5 | Baptist | Scottish | Ontario | No Occupation Listed | 47 |
| 9 | oliver | mary | F | 27 | Baptist | English | Ontario | No Occupation Listed | 47 |
| 12 | oliver | mary | F | 2 | Baptist | Scottish | Ontario | No Occupation Listed | 47 |
| 1 | oliver | robert | M | 16 | Presbyterian Episcopal | Scottish | Ontario | Farmers, general and nfs | 126 |
| 8 | oliver | thomas | M | 35 | Baptist | Scottish | Ontario | Farmers, general and nfs | 47 |
| 11 | oliver | william | M | 3 | Baptist | Scottish | Ontario | No Occupation Listed | 47 |
| 2 | oughtred | ada | F | 3 | Wesleyan Methodist | English | Ontario | No Occupation Listed | 76 |
| 1 | oughtred | grace | F | 5 | Wesleyan Methodist | English | Ontario | No Occupation Listed | 76 |
| 25 | oughtred | jane | F | 42 | Wesleyan Methodist | English | Ontario | No Occupation Listed | 76 |
| 3 | oughtred | jane | F | 1 | Wesleyan Methodist | English | Ontario | No Occupation Listed | 76 |
| 24 | oughtred | william | M | 54 | Wesleyan Methodist | English | England | Farmers, general and nfs | 76 |