Wilhelm August Thams (June 22, 1812 – July 4, 1884) was a Norwegian merchant and mill owner.
Wilhelm Thams was the son of Jacob Thullin Thams (1770–1826), who was a bailiff in Ringerike. He was married to Ida Olava Mandskow, and was the father of Marentius Thams and grandfather of Christian Thams. In 1859, he relocated from Fredrikstad in Østfold where he had sawmill operations and settled in Trondheim.
In 1867, Wilhelm Thams built a sawmill and established a small port which became known as Thamshavn on a side inlet of Trondheimsfjord. He established a timber trading company, Strandheim Brug, in the valley of Orkdalen which his son Marentius would develop to become the largest such company in Norway. In 1868, in cooperation with ship owner Christian Salvesen, he established the Ørkedals Mining Company to develop mining interest in the area around Løkken.