Thomas Alexander Boyd (June 25, 1830 – May 28, 1897) was a U.S. Representative from Illinois. Born near Bedford in Adams County, Pennsylvania, Boyd attended the public schools.He was graduated from Marshall College, Mercersburg, Pennsylvania, in 1848.He studied law in Chambersburg, Pennsylvania.He was admitted to the bar and commenced practice in Bedford, Pennsylvania.He moved to Lewistown, Illinois, in 1856 and engaged in the practice of law until 1861.During the Civil War enlisted in the Seventeenth Regiment, Illinois Infantry, in 1861 and obtained the commission of captain.He served as member of the State senate in 1866 and was reelected in 1870.