Thomas Sanders McMillan (November 27, 1888 – September 29, 1939) was a lawyer and a United States Representative from South Carolina.

He graduated from the Orangeburg Collegiate Institute in 1907 and taught school for the next two years in Perry.

He moved to Charleston where he began the practice of law on January 1, 1915, with James B. Heyward, as well as pursuing his agricultural interests.

In addition, he was the head baseball coach at The Citadel from 1916 to 1919; for five years before law school, he had played professional minor league baseball with the South Atlantic League.

He was re-elected six more times and while in Congress was a member of the executive committee of the Inter-Parliamentary Union from 1937 to 1939.