Thomas Day Singleton (Birth date unknown – November 25, 1833) was a United States Representative from South Carolina. He was born near Kingstree, South Carolina but his birth date is unknown.Singleton was a member of the South Carolina House of Representatives, 1826-1833. He was elected as a Nullifier to the Twenty-third Congress and served without having qualified, from March 3, 1833, until his death in Raleigh, North Carolina, November 25, 1833, while en route to Washington, D.C..