Prior to 2012, the redistribution rules for increasing the number of seats in the House of Commons of Canada was governed by section 51 of the Constitution Act, 1867, as last amended in 1985. As early as 2007, attempts were made to reform the calculation of how that number was determined, as the 1985 formula did not fully take into account the rapid population growth being experienced in the provinces of Alberta, British Columbia and Ontario. The revised formula, as originally presented, was estimated to have the following impact: Three successive bills were presented by the Government of Canada before its final form was passed by the House of Commons and Senate in 2011.
The Act replaced s. 51 of the Constitution Act, 1867 with the following formula:
Divide the estimated population of a province by a determined electoral quotient.
If the number of members determined is less than what a province had in 1985, increase its seat count to that number.
If a province's population was overrepresented in the House of Commons at the completion of the last redistribution process, and would now be under-represented based on the calculations above, it will be given extra seats so that its share of House of Commons seats is proportional to its share of the population.
No province can have fewer MPs than it has Senators.
Otherwise, the calculation determined in 1985 under the Constitution Act, 1985 will govern the amount.
The addition of three seats in Quebec marked the first time since the adoption of Canada's current electoral redistribution formula in 1985 that any province besides Ontario, Alberta and British Columbia has gained new seats.
Process of redistribution
The allocation of seats to the provinces and territories was based on rules in the Constitution of Canada as well as population estimates made by Statistics Canada based on the 2006 Census. A final report was tabled October 2013, with the changes proclaimed to take effect as of the first dissolution of Parliament occurring after May 1, 2014. The names of some ridings were changed the Riding Name Change Act, 2014 came into force on June 19, 2014. In a report issued in 2014 Elections Canada noted: "While some administrative tasks remained to be done after that point, Elections Canada's role of supporting the federal electoral boundaries commissions, which had worked for up to 18 months in their respective provinces, was complete." The report concluded that "the process for the 2012 redistribution of federal electoral boundaries was a success."
Effect of 2013 Representation Orders
Notional change of seats by party ! colspan="2" style="text-align:left;" | Party ! 2011 Election ! Redistributed ! ± ! % ! colspan="2" style="text-align:left;" | Total ! style="text-align:right;" |308 ! style="text-align:right;" |338 ! style="text-align:right;" |+30