Thomas Bassett Macaulay, also known as T. B. Macaulay, (6 June 1860–1942) was born in Hamilton, Ontario, Canada. He was a noted actuary of his era; a philanthropist; and was the founder of the Macaulay Institute, in 1930. It has been estimated that most of the world's Holstein cattle descend from Macaulay's herd.
Thomas Bassett Macaulay was the son of the Scottish born Robertson Macaulay (1833–1915), who emigrated to Canada in 1854. The family were descendants of the Macaulay family of Lewis, and were patrilineal descendants of the 17th century Uig folk-hero Donald Cam Macaulay. Robertson Macaulay married Barbara Marie Reid, and moved his family to Montreal, Quebec, Canada when he was offered a position there with Sun Life Assurance Company. He joined as a secretary in 1874; by 1889 he had worked his way up to president.
Thomas Bassett Macaulay graduated high school and joined Sun Life at the age of 17. For the next forty years he worked for the company as actuary (aged 20), secretary, managing director (46), president (55). He served as president for 20 years, before his retirement as chairman.
Macaulay was a Fellow of the Institute of Actuaries of Great Britain. He was one of four Canadian charter members of the Actuarial Society of America. In 1899, he became the first Canadian to be president of the society; as well as its youngest president, at age 39. When he died in 1942, Macaulay was also the longest surviving charter member. Macaulay represented the actuaries of both Canada and the United States at the International Congresses, held in Paris and Berlin, in the years 1900 and 1906. He was also a Fellow of the Royal Statistical Society, President of the Canadian Life Assurance Officers' Association, and President of the Canadian West Indian League, and became an honorary president of the Navy League of Canada. In 1915 he became president of Sun Life.