The 3rd constituency of Ille-et-Vilaine is a French legislative constituency in the Ille-et-Vilaine département. Like the other 576 French constituencies, it elects one MP using the two-round system, with a run-off if no candidate receives over 50% of the vote in the first round.
Following the 1958 redistricting of French legislative constituencies, Ille-et-Vilaine's 3rd constituency was centered around the commune of Vitré. The department contained 6 constituencies at the time, and the constituency was composed of the following cantons:
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Following the 2010 redistricting of French legislative constituencies, induced by ordinance <abbr>n<sup>o</sup></abbr> 2009-935 of 29 July 2009 and ratified by the French Parliament on 21 January 2010, Ille-et-Vilaine's 3rd constituency contains the following administrative divisions:
The 2012 French legislative elections took place on 10 June 2012 and 17 June 2012, consecutive Sundays.
The 2017 French legislative elections took place on 11 June 2017 and 18 June 2017, consecutive Sundays.
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