Thomas Ash Tomlinson (March 1802 – June 18, 1872) was a U.S. Representative from New York. Born in New York City in March 1802, Tomlinson attended the schools of Champlain and Plattsburgh, New York. He studied law and gained admission to the bar, commencing practice in Keeseville, New York, in 1823. He was a mill owner and dealer in lands, serving as a colonel in the state militia and as a member of the New York State Assembly in 1835 and 1836.