William Mitchell (January 19, 1807 – September 11, 1865) was a United States Representative from Indiana. He was born in Root, New York where he attended the public schools. Later, he studied law and was admitted to the bar in 1836. He moved to Kendallville, Indiana and commenced the practice of law. He was appointed first postmaster of Kendallville on December 7, 1836, and served until a successor was appointed on March 7, 1846.