Residents of Collingwood, Town—Ville — Sub-district C, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 15 | obrien | arthur | M | 32 | Roman Catholic | Irish | Ontario | Clerk, nfs | 271 |
| 17 | obrien | arthur | M | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 271 |
| 13 | obrien | catharine | F | 31 | Presbyterian | English | Ontario | No Occupation Listed | 149 |
| 16 | obrien | frances | F | 27 | Methodist | Irish | Ontario | No Occupation Listed | 271 |
| 23 | obrien | fredrick | M | 35 | Episcopal | English | Ontario | Painters, nfs | 4 |
| 14 | obrien | harry | M | 4 | Presbyterian | Irish | Ontario | No Occupation Listed | 149 |
| 24 | obrien | margaret | F | 27 | Baptist | English | Ontario | No Occupation Listed | 4 |
| 25 | obrien | robert | M | 0 | Episcopal | English | Ontario | No Occupation Listed | 4 |
| 12 | obrien | robt | M | 32 | Presbyterian | Irish | Ontario | Dealer, merchant etc. (Wholesale & retail trade) | 149 |
| 25 | oconnor | norina | F | 20 | Roman Catholic | Irish | Ireland | Dressmakers | 111 |
| 21 | ogrady | james | M | 18 | Roman Catholic | Irish | Ontario | No Occupation Listed | 118 |
| 18 | ogrady | john | M | 50 | Roman Catholic | Irish | Ireland | Occupational title unclassifiable | 118 |
| 19 | ogrady | mary | F | 45 | Roman Catholic | Irish | Ireland | No Occupation Listed | 118 |
| 22 | ogrady | mary | F | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 118 |
| 20 | ogrady | patrick | M | 19 | Roman Catholic | Irish | Ontario | No Occupation Listed | 118 |
| 5 | oharra | aulteney | M | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 120 |
| 8 | oharra | eathel | F | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 120 |
| 9 | oharra | george | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 120 |
| 6 | oharra | john | M | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 120 |
| 4 | oharra | mary | F | 39 | Roman Catholic | English | England | No Occupation Listed | 120 |
| 7 | oharra | mary | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 120 |
| 3 | oharra | thos | M | 40 | Roman Catholic | Irish | Ireland | Labourers nfs | 120 |
| 11 | oliphant | david | M | 33 | Baptist | Scottish | Ontario | Dealer, merchant etc. (Wholesale & retail trade) | 336 |
| 2 | olmstead | allan | M | 7 | Baptist | British | Ontario | No Occupation Listed | 156 |
| 9 | olmstead | cecil | M | 0 | Baptist | British | Ontario | No Occupation Listed | 157 |
| 6 | olmstead | elizabeth | F | 21 | Episcopal | English | Quebec | No Occupation Listed | 157 |
| 7 | olmstead | ernest | M | 5 | Baptist | British | Ontario | No Occupation Listed | 157 |
| 1 | olmstead | eva | F | 10 | Baptist | British | Ontario | No Occupation Listed | 156 |
| 25 | olmstead | frederick | M | 12 | Baptist | British | Ontario | No Occupation Listed | 156 |
| 3 | olmstead | hattie | F | 3 | Baptist | British | Ontario | No Occupation Listed | 156 |
| 24 | olmstead | ida | F | 14 | Baptist | British | United States | No Occupation Listed | 156 |
| 22 | olmstead | oscar | M | 38 | Baptist | Welsh | Quebec | Construction workers nec | 156 |
| 23 | olmstead | rachael | F | 32 | Baptist | Dutch | Ontario | No Occupation Listed | 156 |
| 5 | olmstead | reuben | M | 29 | Baptist | British | Quebec | Carpenters | 157 |
| 4 | olmstead | wellburn | M | 2 | Baptist | British | Ontario | No Occupation Listed | 156 |
| 8 | olmtead | leslie | M | 3 | Baptist | British | Ontario | No Occupation Listed | 157 |
| 12 | olsoon | peter | M | 28 | Presbyterian | Swedish | Sweden | Seamen | 298 |
| 17 | omelia | charles | M | 31 | Methodist | Irish | Ireland | Labourers nfs | 361 |
| 22 | omelia | charles | M | 0 | Methodist | Irish | Ontario | No Occupation Listed | 361 |
| 20 | omelia | john | M | 9 | Methodist | Irish | Ontario | No Occupation Listed | 361 |
| 21 | omelia | may | F | 7 | Methodist | Irish | Ontario | No Occupation Listed | 361 |
| 18 | omelia | sarah | F | 31 | Methodist | Irish | Ireland | No Occupation Listed | 361 |
| 19 | omelia | william | M | 13 | Methodist | Irish | Ontario | No Occupation Listed | 361 |
| 19 | oneil | charles | M | 29 | Episcopal | Irish | Ontario | Gardeners nfs | 96 |
| 23 | oneil | charles | M | 5 | Episcopal | Irish | Ontario | No Occupation Listed | 96 |
| 21 | oneil | margaret | F | 8 | Episcopal | Irish | Ontario | No Occupation Listed | 96 |
| 15 | oneil | margaret | F | 18 | Episcopal | Irish | Ireland | Domestic and House Servants | 117 |
| 20 | oneil | martha | F | 29 | Episcopal | Irish | Ontario | No Occupation Listed | 96 |
| 22 | oneil | martha | F | 6 | Episcopal | Irish | Ontario | No Occupation Listed | 96 |
| 24 | oneil | mary | F | 3 | Episcopal | Irish | Ontario | No Occupation Listed | 96 |
| 25 | oneil | sarah | F | 1 | Episcopal | Irish | Ontario | No Occupation Listed | 96 |
| 8 | orr | catherine | F | 4 | Episcopal | Irish | Ontario | No Occupation Listed | 334 |
| 6 | orr | jinnie | F | 31 | Episcopal | Irish | Ontario | No Occupation Listed | 334 |
| 7 | orr | john | M | 6 | Episcopal | Irish | Ontario | No Occupation Listed | 334 |
| 10 | osullivan | ann | F | 70 | Roman Catholic | Irish | Ireland | No Occupation Listed | 176 |
| 19 | osullivan | annie | F | 27 | Roman Catholic | Irish | Ontario | No Occupation Listed | 23 |
| 21 | osullivan | annie | F | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 23 |
| 18 | osullivan | daniel | M | 35 | Roman Catholic | Irish | Ireland | Carpenters | 23 |
| 11 | osullivan | kate | F | 23 | Roman Catholic | Irish | Ireland | No Occupation Listed | 176 |
| 20 | osullivan | mary | F | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 23 |
| 24 | ougle | amy | F | 2 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 22 | ougle | benj | M | 7 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 16 | ougle | eliza | F | 39 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 17 | ougle | eliza | F | 20 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 23 | ougle | ellen | F | 5 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 21 | ougle | ida | F | 9 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 15 | ougle | john | M | 47 | Methodist | English | England | Stone carvers or cutters and stone yard workers | 42 |
| 20 | ougle | minnie | F | 13 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 25 | ougle | sanfred | M | 0 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 18 | ougle | thomas | M | 17 | Methodist | English | Ontario | No Occupation Listed | 42 |
| 19 | ougle | william | M | 15 | Methodist | English | Ontario | No Occupation Listed | 42 |