Thompson was born in Toronto, the son of Joseph Thompson,[1] and grew up in Toronto's Cabbagetown neighbourhood. He was educated at Dufferin School and Jarvis Collegiate. At 17, he was employed as a clerk in a dry goods store. In 1889, he became a treasury clerk for the city of Toronto. In 1898, he married Ida M. Wilkinson. In 1907, he became Toronto's Commissioner of Industry and Publicity. In 1908, Thompson entered business on his own as an insurance broker.[2] He served as city controller in 1915. He was a captain in the Canadian Expeditionary Force during World War I.[1]
After he left politics in 1929, he was named registrar for the Toronto surrogate court. Thompson lost this appointment in 1934 and returned to the insurance business. In 1939, he ran unsuccessfully for a seat on Toronto city council. He died in Toronto two years later.[2]