Residents of Sheffield — Sub-district D, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 8 | obrien | cathrine | F | 20 | Roman Catholic | Irish | Ontario | No Occupation Listed | 236 |
| 6 | obrien | daniel | M | 50 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 236 |
| 11 | obrien | daniel | M | 16 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 236 |
| 9 | obrien | jerry | M | 19 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 236 |
| 15 | obrien | jerry | M | 52 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 237 |
| 10 | obrien | john | M | 18 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 236 |
| 13 | obrien | joseph | M | 12 | Roman Catholic | Irish | Ontario | No Occupation Listed | 236 |
| 7 | obrien | mandy | F | 44 | Roman Catholic | Irish | Ontario | No Occupation Listed | 236 |
| 12 | obrien | michael | M | 14 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 236 |
| 14 | obrien | rachael | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 236 |
| 10 | odea | cathrine | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 3 |
| 11 | odea | dennis | M | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 3 |
| 14 | odea | james | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 3 |
| 9 | odea | margret | F | 31 | Roman Catholic | Irish | Ontario | No Occupation Listed | 3 |
| 12 | odea | margret | F | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 3 |
| 8 | odea | michael | M | 39 | Roman Catholic | Irish | Ontario | Dealer, merchant etc. (Wholesale & retail trade) | 3 |
| 13 | odea | michael | M | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 3 |
| 11 | onail | barnard | M | 24 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 241 |
| 8 | onail | darby | M | 60 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 241 |
| 9 | onail | hannah | F | 52 | Roman Catholic | Irish | Ireland | No Occupation Listed | 241 |
| 12 | onail | mathew | M | 21 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 241 |
| 13 | onail | patrick | M | 10 | Roman Catholic | Irish | Ontario | No Occupation Listed | 241 |
| 10 | onail | rose | F | 28 | Roman Catholic | Irish | Ontario | No Occupation Listed | 241 |
| 17 | otterkirk | caroline | F | 47 | Wesleyan Methodist | German | United States | No Occupation Listed | 434 |
| 23 | otterkirk | elinia | F | 1 | Wesleyan Methodist | German | Ontario | No Occupation Listed | 435 |
| 20 | otterkirk | emer | M | 1 | Wesleyan Methodist | German | Ontario | No Occupation Listed | 434 |
| 18 | otterkirk | ervan | M | 13 | Wesleyan Methodist | German | Ontario | No Occupation Listed | 434 |
| 22 | otterkirk | eveline | F | 21 | Wesleyan Methodist | German | Ontario | No Occupation Listed | 435 |
| 19 | otterkirk | frances | F | 21 | Wesleyan Methodist | German | Ontario | No Occupation Listed | 434 |
| 16 | otterkirk | isaac | M | 50 | Wesleyan Methodist | German | United States | Farmers, general and nfs | 434 |
| 21 | otterkirk | isiah | M | 28 | Wesleyan Methodist | German | Ontario | Farmers, general and nfs | 435 |