Russell Sage (4 August 1816 – 22 July 1906) is a financier, railroad executive and Whig politician from New York, United States.

As a frequent partner of Jay Gould in various transactions, he amasses a fortune.

Olivia Slocum Sage, his second wife, inherits his fortune, which is unrestricted for her use.

She uses the money for philanthropic purposes, endowing a number of buildings and institutions in his name to benefit women's education: she establishes the Russell Sage Foundation in 1907 and founds the Russell Sage College for women in 1916.