After a short stay at the California Institute of Technology at Pasadena as guests of Olga Taussky-Todd, Heilbronn and his wife moved to Toronto where he was appointed to a chair of mathematics at Toronto University. Heilbronn became a Canadian citizen in 1970 and spent the rest of his life in Canada, taking an active part national role in mathematics there.
Pagkatapos ng isang maikling manatili sa California Institute of Technology sa Pasadena bilang ng mga bisita Olga Taussky-Todd, Heilbronn at kanyang asawa ang inilipat sa Toronto kung saan siya ay hihirangin upang angkinin ang isang upuan ng matematika sa Toronto University. Heilbronn ay naging isang mamamayan ng Canada sa 1970 at ginugol ang natitirang bahagi ng kanyang buhay sa Canada, pagtanggap ng aktibong papel sa pambansang bahagi matematika doon.