One of the commonest webcaps of southern Australia, Cortinarius archeri is distributed from Queensland, through to South Australia and Western Australia. Around Sydney it has been found in Oatley, Howes Valley and Tari Creek in Windsor, as well as Boronia Park. It is regularly seen in the Lane Cove National Park, especially around North Ryde. In Victoria, the species is at Morwell National Park. This is the only Cortinarius species that was found in the Field Naturalists Club of Victoria's first fungi foray to Coranderrk Bush Sanctuary. It is found in the Mount Lofty Ranges east of Adelaide in South Australia. It has been found at Mundaring in Western Australia. In Tasmania, it has been recorded from the wet forests, dry forests and cleared areas, from Mount Wellington and Mount Field National Parks, as well as Bruny Island.