Residents of Nottawasaga — Sub-district A, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 2 | oben | abraham | M | 14 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 1 | oben | barbara | F | 33 | Mennonite | German | Ontario | No Occupation Listed | 420 |
| 8 | oben | clementine | F | 1 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 6 | oben | ella | F | 5 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 25 | oben | john | M | 39 | Mennonite | French | Quebec | Farmers, general and nfs | 420 |
| 4 | oben | lewis | M | 9 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 7 | oben | nancy | F | 3 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 5 | oben | wesley | M | 7 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 3 | oben | william | M | 12 | Mennonite | French | Ontario | No Occupation Listed | 420 |
| 21 | obrine | andrew | M | 56 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 316 |
| 22 | obrine | jane | F | 58 | Anglican | Irish | Ireland | No Occupation Listed | 316 |
| 2 | oconnell | catharine | F | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 194 |
| 1 | oconnell | ellen | F | 20 | Roman Catholic | Irish | Ontario | No Occupation Listed | 194 |
| 25 | oconnell | patrick | M | 60 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 194 |
| 16 | oconner | catharine | F | 55 | Roman Catholic | Irish | Ireland | No Occupation Listed | 183 |
| 18 | oconner | catharine | F | 20 | Roman Catholic | Irish | Ontario | No Occupation Listed | 183 |
| 15 | oconner | edward | M | 60 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 183 |
| 19 | oconner | edward | M | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 183 |
| 17 | oconner | john | M | 24 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 183 |
| 16 | odonnal | alace | F | 30 | Roman Catholic | Irish | Ontario | No Occupation Listed | 115 |
| 19 | odonnal | alace | F | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 115 |
| 17 | odonnal | ellen | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 115 |
| 18 | odonnal | john | M | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 115 |
| 15 | odonnal | thomas | M | 30 | Roman Catholic | Irish | Ontario | Labourers nfs | 115 |
| 22 | ody | frederick | M | 26 | Anglican | English | England | Clerks in shops and stores | 359 |
| 4 | ohara | dorathea | F | 14 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 6 | ohara | eloe | M | 10 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 1 | ohara | george | M | 21 | Anglican | Irish | Ontario | river drivers | 53 |
| 5 | ohara | libbie | F | 12 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 8 | ohara | margaret | F | 6 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 7 | ohara | mary | F | 8 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 3 | ohara | sarah | F | 17 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 9 | ohara | susan | F | 4 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 24 | ohara | susanna | F | 45 | Anglican | Irish | Ireland | No Occupation Listed | 53 |
| 23 | ohara | thomas | M | 45 | Anglican | Irish | United States | Carpenters | 53 |
| 2 | ohara | walter | M | 19 | Anglican | Irish | Ontario | No Occupation Listed | 53 |
| 25 | ohara | william | M | 23 | Anglican | Irish | Ontario | Labourers nfs | 53 |
| 21 | ohare | dennis | M | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 17 | ohare | ellen | F | 36 | Roman Catholic | Irish | Ireland | No Occupation Listed | 516 |
| 23 | ohare | ellen | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 18 | ohare | john | M | 16 | Roman Catholic | Irish | Ontario | Manufacturers | 516 |
| 24 | ohare | margaret | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 20 | ohare | mary | F | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 1 | ohare | maud | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 16 | ohare | micheal | M | 39 | Roman Catholic | Irish | Ireland | Manufacturers | 516 |
| 22 | ohare | micheal | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 19 | ohare | patrick | M | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 25 | ohare | sarah | F | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 516 |
| 25 | oils | mary | F | 6 | Presbyterian | Scottish | Ontario | No Occupation Listed | 411 |
| 13 | olary | annie | F | 17 | Roman Catholic | Irish | United States | Seamstress | 417 |
| 14 | olary | daniel | M | 15 | Roman Catholic | Irish | United States | No Occupation Listed | 417 |
| 3 | omalley | andrew | M | 17 | Roman Catholic | Irish | United States | No Occupation Listed | 125 |
| 24 | omalley | ann | F | 52 | Roman Catholic | Irish | Ireland | No Occupation Listed | 125 |
| 25 | omalley | bridget | F | 22 | Roman Catholic | Irish | United States | No Occupation Listed | 125 |
| 2 | omalley | james | M | 18 | Roman Catholic | Irish | United States | No Occupation Listed | 125 |
| 1 | omalley | margaret | F | 20 | Roman Catholic | Irish | United States | No Occupation Listed | 125 |
| 15 | omalley | mary | F | 24 | Roman Catholic | Irish | Ontario | No Occupation Listed | 156 |
| 23 | omalley | patrick | M | 54 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 125 |
| 14 | omalley | patrick | M | 25 | Roman Catholic | Irish | United States | Dealer, merchant etc. (Wholesale & retail trade) | 156 |
| 18 | organ | orvilla | F | 15 | Methodist | English | Ontario | No Occupation Listed | 135 |
| 15 | osborne | benjamin | M | 14 | Presbyterian | Irish | Ontario | No Occupation Listed | 372 |
| 13 | osborne | daniel | M | 18 | Presbyterian | Irish | Ontario | Farmers, general and nfs | 372 |
| 21 | osborne | david | M | 5 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 16 | osborne | eliza | F | 12 | Presbyterian | Irish | Ontario | No Occupation Listed | 372 |
| 18 | osborne | emma | F | 9 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 23 | osborne | frances | F | 1 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 3 | osborne | george | M | 23 | Presbyterian | Irish | Ontario | Farmers, general and nfs | 427 |
| 22 | osborne | james | M | 0 | Anglican | Irish | Ontario | No Occupation Listed | 373 |
| 12 | osborne | jane | F | 50 | Presbyterian | Irish | United States | No Occupation Listed | 372 |
| 17 | osborne | john | M | 10 | Presbyterian | Irish | Ontario | No Occupation Listed | 372 |
| 15 | osborne | john | M | 35 | Methodist | English | Ontario | Farmers, general and nfs | 382 |
| 20 | osborne | john | M | 7 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 20 | osborne | mary | F | 26 | Anglican | Irish | Ontario | No Occupation Listed | 373 |
| 21 | osborne | mary | F | 1 | Anglican | Irish | Ontario | No Occupation Listed | 373 |
| 16 | osborne | mary | F | 35 | Methodist | English | England | No Occupation Listed | 382 |
| 4 | osborne | matilda | F | 20 | Presbyterian | Irish | Ontario | No Occupation Listed | 427 |
| 22 | osborne | petar | M | 3 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 14 | osborne | robert | M | 16 | Presbyterian | Irish | Ontario | Farmers, general and nfs | 372 |
| 18 | osborne | sarah | F | 7 | Presbyterian | Irish | Ontario | No Occupation Listed | 372 |
| 19 | osborne | sarah | F | 8 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 17 | osborne | thomas | M | 11 | Methodist | English | Ontario | No Occupation Listed | 382 |
| 11 | osborne | william | M | 50 | Anglican | Irish | Ontario | Farmers, general and nfs | 372 |
| 19 | osborne | william | M | 26 | Anglican | Irish | Ontario | Farmers, general and nfs | 373 |
| 14 | ovas | alexander | M | 69 | Presbyterian | Dutch | Scotland | Farmers, general and nfs | 79 |
| 17 | ovas | bethia | F | 21 | Presbyterian | Dutch | Ontario | No Occupation Listed | 79 |
| 15 | ovas | charlotte | F | 60 | Presbyterian | Irish | Ireland | No Occupation Listed | 79 |
| 18 | ovas | julia | F | 19 | Presbyterian | Dutch | Ontario | No Occupation Listed | 79 |
| 16 | ovas | latitia | F | 27 | Presbyterian | Dutch | Ontario | No Occupation Listed | 79 |
| 13 | ovens | archibald | M | 3 | Anglican | Irish | Ontario | No Occupation Listed | 302 |
| 6 | ovens | charlotte | F | 18 | Anglican | Irish | Ontario | No Occupation Listed | 462 |
| 4 | ovens | eliza | F | 27 | Anglican | Irish | Ontario | No Occupation Listed | 134 |
| 15 | ovens | eveline | F | 0 | Anglican | Irish | Ontario | No Occupation Listed | 302 |
| 7 | ovens | george | M | 16 | Anglican | Irish | Ontario | No Occupation Listed | 462 |
| 5 | ovens | henry | M | 21 | Anglican | Irish | Ontario | Farmers, general and nfs | 462 |
| 4 | ovens | margaret | F | 55 | Anglican | Irish | Ireland | No Occupation Listed | 462 |
| 12 | ovens | mary | F | 5 | Anglican | Irish | Ontario | No Occupation Listed | 302 |
| 11 | ovens | sarah | F | 30 | Anglican | Scottish | Ontario | No Occupation Listed | 302 |
| 3 | ovens | thomas | M | 26 | Anglican | Irish | Ontario | Farmers, general and nfs | 134 |
| 3 | ovens | thomas | M | 57 | Anglican | Irish | Ireland | Farmers, general and nfs | 462 |
| 14 | ovens | thomas | M | 2 | Anglican | Irish | Ontario | No Occupation Listed | 302 |
| 10 | ovens | william | M | 32 | Anglican | Irish | Ontario | Farmers, general and nfs | 302 |