The list of by-elections in the Province of Canada includes every by-election held in the Province of Canada from its creation in 1841 until Confederation in 1867. By-elections occurred whenever there was a vacancy in the Legislative Assembly. The Legislative Council was made an elective body in 1856 and by-elections occurred there as well. Due to the fluid nature of party allegiances during this time no attempt has been made to show them in this list.

A by-election occurs whenever there was a vacancy in the legislature. Vacancies occurred for the following reasons:

• Death of a member.
• Resignation of a member.
• Voided results
• Expulsion from the legislature.
• Ineligibility to sit.
• Appointment to the Legislative Council, the appointed upper house, which was made elective in 1856.
• Ministerial by-elections occurred when incumbent members recontested their seats upon being appointed to the Executive Council. In 1853 this requirement was amended to exempt Executive Councillors who resigned their offices and within a month accepted a new office. Solicitors General were not exempted if they switched to the Attorney Generalship.^[1] In 1855 this exception was dropped.^[2] In 1857 this requirement was extended to include Legislative Councillors.^[3]

* Incumbents sat for Quebec City which was a three-member seat until 1860 when it was split into Centre, East and West districts. As a result, the by-elections were held for the new single-member seats

** Members of the Brown-Dorion Ministry of August 2–4, 1858

The Legislative Council became an elective body in 1856. By-elections were held to fill vacancies. In 1857 Legislative Councillors appointed to office were now required to seek re-election at Ministerial by-elections.