A by-election was held in the federal riding of Chicoutimi—Le Fjord in Quebec on June 18, 2018, following the resignation of incumbent Liberal MP Denis Lemieux. The seat was gained by the Conservative Party of Canada, with Richard Martel winning on a large swing of 19 points, becoming the new MP. The result was a surprise as in the 2015 election, the conservative candidate had come in 4th place. Martel's victory was the first by-election loss for the Liberals since 2013.