Records of forty-eight new or noteworthy lichens, allied fungi or lichenicolous fungi from Québec are presented. The majority of specimens were collected during opportunistic field visits and inventories conducted between 2014 and 2023. Additionally, we include previously undocumented specimens, either collected in earlier years or more recently, that have not yet been reported or have been mentioned only once in the literature. The species Cercidospora epipolytropa, Leptorhaphis lucida, Naetrocymbe rhyponta, Peccania tiruncula, Pyrenidium aggregatum, Pyrenopsis grumulifera, Tremella flavoparmeliae and Trimmatothelopsis dispersa are new to Canada. Thirty additional species are reported as new to Québec: Rimularia badioatra and Umbilicaria hirsuta. These findings highlight the need for ongoing efforts to deepen our understanding of lichen distributions in southern Québec, a region that remains largely underexplored. Keywords: Biodiversity, distribution, range extension, rare species.