Residents of Québec, Montcalm (W.—O.), Ward—Quartier — Sub-district H, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 9 | obrien | jhn | M | 36 | Roman Catholic | Irish | Quebec | No Occupation Listed | 306 |
| 10 | obrien | mary | F | 39 | Roman Catholic | Irish | Ireland | No Occupation Listed | 306 |
| 1 | oconnell | estella | F | 3 | Roman Catholic | Irish | Quebec | No Occupation Listed | 190 |
| 25 | oconnell | fredrick | M | 8 | Roman Catholic | Irish | Quebec | No Occupation Listed | 190 |
| 19 | oconnell | margaret | F | 54 | Roman Catholic | Irish | Ireland | No Occupation Listed | 349 |
| 24 | oconnell | mrs | F | 28 | Roman Catholic | Irish | Quebec | No Occupation Listed | 190 |
| 18 | oconnell | richard | M | 64 | Roman Catholic | Irish | Ireland | Ambiguous responses | 349 |
| 2 | oconnell | william | M | 1 | Roman Catholic | Irish | Quebec | No Occupation Listed | 190 |
| 21 | odonnelle | james | M | 48 | Roman Catholic | Irish | Ireland | No Occupation Listed | 191 |
| 23 | odonnelle | john | M | 19 | Roman Catholic | Irish | Quebec | No Occupation Listed | 191 |
| 1 | odonnelle | louis | M | 8 | Roman Catholic | Irish | Quebec | No Occupation Listed | 191 |
| 25 | odonnelle | margarett | F | 14 | Roman Catholic | Irish | Quebec | No Occupation Listed | 191 |
| 22 | odonnelle | mary | F | 47 | Roman Catholic | Irish | Quebec | No Occupation Listed | 191 |
| 24 | odonnelle | rose | F | 16 | Roman Catholic | Irish | Quebec | No Occupation Listed | 191 |
| 2 | odonnelle | william | M | 6 | Roman Catholic | Irish | Quebec | No Occupation Listed | 191 |
| 19 | odonovan | john | M | 50 | Roman Catholic | Irish | Quebec | Labourers nfs | 108 |
| 11 | odonovan | margaret | F | 19 | Roman Catholic | Irish | Quebec | Clerk, nfs | 108 |
| 10 | odonovan | mary | F | 52 | Roman Catholic | Irish | Quebec | No Occupation Listed | 108 |
| 12 | odonovan | mary | F | 18 | Roman Catholic | Irish | Quebec | Clerk, nfs | 108 |
| 13 | odonovan | matilda | F | 14 | Roman Catholic | Irish | Quebec | No Occupation Listed | 108 |
| 10 | odowd | francis | M | 19 | Roman Catholic | Irish | Quebec | Watchmen and guards | 2 |
| 9 | odowd | helene | F | 56 | Roman Catholic | Irish | Ireland | No Occupation Listed | 2 |
| 8 | odowd | john | M | 60 | Roman Catholic | Irish | Ireland | Watchmen and guards | 2 |
| 17 | ofarrell | catherine | F | 32 | Roman Catholic | Irish | Ontario | No Occupation Listed | 354 |
| 18 | ofarrell | emma | F | 20 | Roman Catholic | Irish | Quebec | Teachers (unspecified) | 354 |
| 16 | ofarrell | patrick | M | 56 | Roman Catholic | Irish | Quebec | Stationary firemen and firemen nfs | 354 |
| 19 | ofarrell | patrick | M | 14 | Roman Catholic | Irish | Quebec | Clerk, nfs | 354 |
| 9 | ogrady | helen | F | 28 | Roman Catholic | Irish | Ireland | No Occupation Listed | 265 |
| 10 | oneil | mary | F | 36 | Roman Catholic | Irish | Ireland | Servants nfs | 19 |
| 24 | orielly | maryanne | F | 26 | Roman Catholic | Irish | Quebec | Servants nfs | 18 |
| 2 | orkney | catherine | F | 25 | Anglican | English | Quebec | No Occupation Listed | 372 |
| 1 | orkney | ellen | F | 26 | Anglican | English | Quebec | No Occupation Listed | 372 |
| 3 | orkney | john | M | 77 | Anglican | English | Quebec | Dealer, merchant etc. (Wholesale & retail trade) | 372 |
| 25 | orkney | william | M | 42 | Anglican | English | Quebec | Railway agents (US) and clerks | 372 |
| 14 | orourke | bridget | F | 70 | Roman Catholic | Irish | Quebec | No Occupation Listed | 278 |
| 4 | orourke | bridget | F | 67 | Roman Catholic | Irish | Ireland | No Occupation Listed | 145 |
| 13 | orourke | henry | M | 80 | Roman Catholic | Irish | Quebec | Labourers nfs | 278 |
| 5 | orourke | ida | F | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 145 |
| 4 | ouellet | marie | F | 45 | Roman Catholic | French | Quebec | No Occupation Listed | 351 |
| 14 | overell | helen | F | 45 | Presbyterian | Scottish | Quebec | No Occupation Listed | 74 |