| By-election | Date | Incumbent | Party | Winner | Party | Cause | Retained |
|---|
| Victoria South | December 18, 1890 | Adam Hudspeth | | Conservative | Charles Fairbairn | | Liberal-Conservative | Death | Yes |
| Napierville | December 9, 1890 | Louis Sainte-Marie | | Liberal | François-Xavier Paradis | | Conservative | Resigned to enter provincial politics in Quebec. | No |
| Kent | July 31, 1890 | Pierre-Amand Landry | | Conservative | Édouard H. Léger | | Conservative | Appointed a judge in the county court of Westmorland and Kent. | Yes |
| Montmorency | July 25, 1890 | Charles Langelier | | Liberal | Louis-Georges Desjardins | | Conservative | Resignation to enter provincial politics in Quebec. | No |
| New Westminster | June 19, 1890 | Donald Chisholm | | Conservative | Gordon Edward Corbould | | Conservative | Death | Yes |
| Lincoln and Niagara | May 23, 1890 | John Charles Rykert | | Conservative | John Charles Rykert | | Conservative | Resignation to recontest over charges of corruption. | Yes |
| Ottawa (City of) (electoral district) | April 26, 1890 | William Goodhue Perley | | Conservative | Charles Herbert Mackintosh | | Conservative | Death | Yes |
| Haldimand | February 20, 1890 | Charles Wesley Colter | | Liberal | Walter Humphries Montague | | Conservative | Election declared void. | No |
| Stanstead | December 18, 1889 | Charles Carroll Colby | | Liberal-Conservative | Charles Carroll Colby | | Liberal-Conservative | Recontested upon appointment as President of the Privy Council. | Yes |
| Victoria | October 28, 1889 | Edgar Crow Baker | | Conservative | Thomas Earle | | Conservative | Resignation. | Yes |
| Compton | May 16, 1889 | John Henry Pope | | Liberal-Conservative | Rufus Henry Pope | | Conservative | Death | Yes |
| Haldimand | January 30, 1889 | Walter Humphries Montague | | Conservative | Charles Wesley Colter | | Liberal | Election declared void. | No |
| Provencher | January 24, 1889 | Joseph Royal | | Conservative | Alphonse Alfred Clément Larivière | | Conservative | AppointedLieutenant-Governor of the North West Territories. | Yes |
| Joliette | January 16, 1889 | Édouard Guilbault | | Conservative | Hilaire Neveu | | Nationalist | Election declared void. | No |
| Cumberland | December 26, 1888 | Arthur Rupert Dickey | | Conservative | Arthur Rupert Dickey | | Conservative | Election declared void. | Yes |
| Cariboo | November 22, 1888 | James Reid | | Liberal-Conservative | Francis Stillman Barnard | | Conservative | Called to the Senate. | Yes |
| Northumberland East | November 21, 1888 | Edward Cochrane | | Conservative | Edward Cochrane | | Conservative | Election declared void. | Yes |
| Shelburne | October 22, 1888 | John Wimburne Laurie | | Conservative | John Wimburne Laurie | | Conservative | Election declared void. | Yes |
| Cardwell | October 3, 1888 | Thomas White | | Conservative | Robert Smeaton White | | Conservative | Death | Yes |
| Montreal East | September 26, 1888 | Charles-Joseph Coursol | | Conservative | Alphonse-Télesphore Lépine | | Independent Conservative | Death | No |
| Assiniboia East | September 12, 1888 | William Dell Perley | | Conservative | Edgar Dewdney | | Conservative | Called to the Senate | Yes |
| Halton | August 22, 1888 | John Waldie | | Conservative | David Henderson | | Conservative | Election declared void. | No |
| Lanark South | August 15, 1888 | John Graham Haggart | | Liberal | John Graham Haggart | | Conservative | Recontested upon appointment as Postmaster-General. | Yes |
| Colchester | August 15, 1888 | Archibald McLelan | | Conservative | Adams George Archibald | | Liberal-Conservative | AppointedLieutenant-Governor of Nova Scotia. | Yes |
| Nicolet | July 17, 1888 | Athanase Gaudet | | Nationalist Conservative | Fabien Boisvert | | Independent Conservative | Death | No |
| Cumberland | July 13, 1888 | Charles Tupper | | Conservative | Arthur Rupert Dickey | | Conservative | AppointedCanadian High Commissioner to the United Kingdom. | Yes |
| Pictou | June 18, 1888 | Charles Hibbert Tupper | | Conservative | Charles Hibbert Tupper | | Conservative | Recontested upon appointment as Minister of Marine and Fisheries. | Yes |
| Russell | May 7, 1888 | William C. Edwards | | Liberal | William C. Edwards | | Liberal | Election declared void. | Yes |
| Kent | May 2, 1888 | Archibald Campbell | | Liberal | Archibald Campbell | | Liberal | Election declared void. | Yes |
| L'Assomption | April 3, 1888 | Joseph Gauthier | | Liberal | Joseph Gauthier | | Liberal | Election declared void. | Yes |
| Missisquoi | March 27, 1888 | George Clayes | | Liberal | Daniel Bishop Meigs | | Liberal | Death | Yes |
| Prince Edward | March 19, 1888 | John Milton Platt | | Liberal | John Milton Platt | | Liberal | Election declared void. | Yes |
| Hastings West | March 17, 1888 | Alexander Robertson | | Conservative | Henry Corby, Jr. | | Conservative | Death | Yes |
| Middlesex West | March 10, 1888 | William Frederick Roome | | Conservative | William Frederick Roome | | Conservative | Election declared void. | Yes |
| Halton | February 7, 1888 | John Waldie | | Liberal | David Henderson | | Conservative | Election declared void. | No |
| Carleton | February 1, 1888 | John A. Macdonald | | Liberal-Conservative | George Lemuel Dickinson | | Conservative | Chose to sit for Kingston. | Yes |
| Victoria | January 23, 1888 | Noah Shakespeare | | Conservative | Edward Gawler Prior | | Conservative | Appointed Postmaster of Victoria. | Yes |
| Queen's | January 18, 1888 | George Gerald King | | Liberal | George Frederick Baird | | Conservative | Election declared void. | No |
| Dorchester | January 7, 1888 | Henri Jules Juchereau Duchesnay | | Nationalist Conservative | Honoré-Julien-Jean-Baptiste Chouinard | | Conservative | Death | No |
| Northumberland East | December 22, 1887 | Albert Mallory | | Liberal | Edward Cochrane | | Conservative | Election declared void. | No |
| Shelburne | December 15, 1887 | Thomas Robertson | | Liberal | John Wimburne Laurie | | Conservative | Election declared void. | No |
| Yarmouth | December 15, 1887 | John Lovitt | | Liberal | John Lovitt | | Liberal | Election declared void. | Yes |
| Victoria | November 21, 1887 | Charles James Campbell | | Conservative | John Archibald McDonald | | Liberal | Election declared void. | No |
| Haldimand | November 12, 1887 | Walter Humphries Montague | | Conservative | Walter Humphries Montague | | Conservative | Election declared void. | Yes |
| Cumberland | November 9, 1887 | Charles Tupper | | Conservative | Charles Tupper | | Conservative | Election declared void. | Yes |
| Colchester | October 27, 1887 | Archibald McLelan | | Conservative | Archibald McLelan | | Conservative | Election declared void. | Yes |
| Bruce West | October 19, 1887 | Edward Blake | | Liberal | James Rowand | | Liberal | Chose to sit for Durham West. | Yes |
| Richelieu | October 18, 1887 | Jean-Baptiste Labelle | | Conservative | Joseph-Aimé Massue | | Conservative | Death | Yes |
| Charlevoix | September 28, 1887 | Simon-Xavier Cimon | | Conservative | Simon Cimon | | Conservative | Death | Yes |
| Renfrew South | August 2, 1887 | Robert Campbell | | Liberal | John Ferguson | | Independent | Death | No |
| Digby | July 16, 1887 | John Campbell | | Conservative | Herbert Ladd Jones | | Conservative | Death | Yes |
| Restigouche | May 21, 1887 | Robert Moffat | | Conservative | George Moffat Jr. | | Conservative | Death | Yes |
| Victoria South | April 20, 1887 | Adam Hudspeth | | Conservative | Adam Hudspeth | | Liberal-Conservative | Seeks re-election due to holding the office of revising officer. | Yes |
| Bruce East | April 2, 1887 | Henry Cargill | | Conservative | Henry Cargill | | Conservative | Seeks re-election due to holding the position of postmaster. | Yes |