Residents of Ops — Sub-district A, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 14 | oboyle | austin | M | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 16 | oboyle | lorretta | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 13 | oboyle | margret | F | 35 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 17 | oboyle | mary | F | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 12 | oboyle | walter | M | 35 | Roman Catholic | Irish | Ireland | Teachers (unspecified) | 116 |
| 15 | oboyle | william | M | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 4 | obrine | alberte | F | 3 | Methodist | English | Ontario | No Occupation Listed | 141 |
| 3 | obrine | ann | F | 35 | Methodist | English | Ontario | No Occupation Listed | 141 |
| 11 | obrine | bridget | F | 29 | Roman Catholic | Irish | Ontario | No Occupation Listed | 163 |
| 13 | obrine | bridget | F | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 163 |
| 10 | obrine | daniel | M | 38 | Roman Catholic | Irish | Ireland | No Occupation Listed | 163 |
| 6 | obrine | hannah | F | 26 | Roman Catholic | Irish | Ontario | No Occupation Listed | 162 |
| 12 | obrine | john | M | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 163 |
| 7 | obrine | macheal | M | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 162 |
| 8 | obrine | patrick | M | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 162 |
| 5 | obrine | thomas | M | 30 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 162 |
| 5 | obrine | william | M | 2 | Methodist | English | Ontario | No Occupation Listed | 141 |
| 3 | oconnel | joseph | M | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 52 |
| 1 | oconnel | mary | F | 29 | Roman Catholic | Irish | Ontario | No Occupation Listed | 52 |
| 2 | oconnel | mary | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 52 |
| 16 | oconnel | theressa | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 135 |
| 13 | oconnell | ann | F | 68 | Roman Catholic | Irish | Ireland | No Occupation Listed | 183 |
| 7 | oconnell | bart | M | 25 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 183 |
| 8 | oconnell | bridget | F | 27 | Roman Catholic | Irish | Ontario | No Occupation Listed | 183 |
| 9 | oconnell | cathrine | F | 23 | Roman Catholic | Irish | Ontario | No Occupation Listed | 183 |
| 8 | oconnell | cecilia | F | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 4 |
| 4 | oconnell | daniel | M | 39 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 118 |
| 10 | oconnell | eliza | F | 21 | Roman Catholic | Irish | Ontario | No Occupation Listed | 183 |
| 9 | oconnell | frances | F | 19 | Roman Catholic | Irish | Ontario | No Occupation Listed | 4 |
| 7 | oconnell | hannah | F | 50 | Roman Catholic | Irish | Ireland | No Occupation Listed | 4 |
| 24 | oconnell | honoria | F | 65 | Roman Catholic | Irish | Ireland | No Occupation Listed | 52 |
| 6 | oconnell | john | M | 23 | Roman Catholic | Irish | Ontario | Labourers nfs | 4 |
| 12 | oconnell | john | M | 70 | Roman Catholic | Irish | Ireland | No Occupation Listed | 183 |
| 6 | oconnell | mary | F | 56 | Roman Catholic | Irish | Ireland | No Occupation Listed | 53 |
| 7 | oconnell | mary | F | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 53 |
| 23 | oconnell | moris | M | 65 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 52 |
| 6 | oconnell | patrick | M | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 118 |
| 25 | oconnell | patrick | M | 25 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 52 |
| 5 | oconnell | patrick | M | 59 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 53 |
| 8 | oconnell | patrick | M | 18 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 53 |
| 5 | oconnell | selia | F | 35 | Roman Catholic | Irish | Ontario | No Occupation Listed | 118 |
| 11 | oconnell | susannah | F | 19 | Roman Catholic | Irish | Ontario | No Occupation Listed | 183 |
| 22 | ogilive | isabella | F | 10 | Methodist | Irish | Ontario | No Occupation Listed | 266 |
| 7 | oharra | francis | M | 63 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 158 |
| 8 | oharra | hanorah | F | 70 | Roman Catholic | Irish | Ireland | No Occupation Listed | 158 |
| 11 | oharra | patrick | M | 16 | Roman Catholic | Irish | Ontario | river drivers | 173 |
| 23 | ohlonoran | annie | F | 10 | Roman Catholic | Irish | Ontario | No Occupation Listed | 158 |
| 22 | ohlonoran | cathrine | F | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 158 |
| 24 | ohlonoran | john | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 158 |
| 25 | ohlonoran | mary | F | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 158 |
| 20 | ohlonoran | micheal | M | 44 | Roman Catholic | Irish | Ireland | Butchers | 158 |
| 21 | ohlonoran | rosann | F | 35 | Roman Catholic | Irish | Ontario | No Occupation Listed | 158 |
| 24 | okeefe | francess | F | 19 | Roman Catholic | Irish | Ireland | Servants nfs | 125 |
| 19 | okeefe | johannah | F | 64 | Roman Catholic | Irish | Ireland | No Occupation Listed | 164 |
| 13 | olaughlan | john | M | 18 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 143 |
| 14 | olaughlan | margret | F | 50 | Roman Catholic | Irish | Ireland | No Occupation Listed | 143 |
| 15 | olaughlan | mary | F | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 143 |
| 13 | omelia | james | M | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 120 |
| 22 | oneil | agnes | F | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 51 |
| 8 | oneil | ann | F | 43 | Anglican | Irish | Ontario | No Occupation Listed | 235 |
| 11 | oneil | bridget | F | 25 | Roman Catholic | Irish | Ontario | No Occupation Listed | 194 |
| 11 | oneil | henry | M | 11 | Anglican | Irish | Ontario | No Occupation Listed | 235 |
| 12 | oneil | john | M | 23 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 194 |
| 10 | oneil | margret | F | 60 | Roman Catholic | Irish | Ireland | No Occupation Listed | 194 |
| 11 | oneil | micheal | M | 21 | Roman Catholic | Irish | Ontario | river drivers | 190 |
| 9 | oneil | patrick | M | 60 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 194 |
| 21 | oneil | thomas | M | 26 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 51 |
| 10 | oneil | thomas | M | 15 | Anglican | Irish | Ontario | No Occupation Listed | 235 |
| 5 | oneil | william | M | 18 | Anglican | Irish | Ontario | river drivers | 132 |
| 9 | oneil | william | M | 18 | Anglican | Irish | Ontario | No Occupation Listed | 235 |
| 18 | oragan | john | M | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 91 |
| 14 | oriley | james | M | 50 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 36 |
| 17 | oriley | james | M | 14 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 36 |
| 15 | oriley | mary | F | 60 | Roman Catholic | Irish | Ireland | No Occupation Listed | 36 |
| 19 | oriley | mary | F | 21 | Roman Catholic | Irish | Ontario | No Occupation Listed | 36 |
| 16 | oriley | patrick | M | 19 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 36 |
| 18 | oriley | sarah | F | 20 | Roman Catholic | Irish | Ontario | No Occupation Listed | 36 |
| 15 | orr | elizabeth | F | 9 | Presbyterian | Irish | Ontario | No Occupation Listed | 236 |
| 16 | orr | robert | M | 35 | Presbyterian | Irish | Ontario | No Occupation Listed | 236 |