William Ludgate (March 11, 1836–June 14, 1912) was a Captain in the Union Army and a Medal of Honor recipient for his actions in the American Civil War. Ludgate joined the Army from New York City in May 1861, and was assigned to the 82nd New York Infantry, rising to the rank of Sergeant Major. He re-enlisted as a veteran in March 1864, and transferred to the 59th New York Infantry, where he was commissioned as an officer in September 1864. He was ultimately discharged in June 1865.