Five new species from Cortinarius sect. Cortinarius are formally described, four from the Americas (Cortinarius palatinus Harrower, sp. nov., Cortinarius atrotomentosus Harrower, sp. nov., Cortinarius altissimus Harrower & T.W. Henkel, sp. nov., Cortinarius neotropicus Harrower, sp. nov.) and one from Australasia (Cortinarius carneipallidus Harrower & E. Horak, sp. nov.) based on molecular, morphological, and ecological circumscription. Additional collections of the Australasian species Cortinarius hallowellensis Wood and Cortinarius kioloensis Wood reveal wider host associations and geographic ranges than previously recorded. Morphological descriptions, photomicrographs and a dichotomous key to all species in Cortinarius sect. Cortinarius are provided. This work raises the number of species in sect. Cortinarius to twelve.