Sumner Baldwin (March 8, 1833 in Ithaca, Tompkins County, New York – January 26, 1903[1]) was an American merchant, banker and politician from New York.
He attended the common schools. In 1856, he removed to Wellsville, and became a partner in his brother's grocery store. In 1866, the brothers sold the store, and engaged in tanning instead. In 1869, they sold the tanning plant, and opened the Bank of Wellsville.
In politics, he was a Republican. He was Supervisor of the Town of Wellsville for seven years.
He was a member of the New York State Assembly (Allegany Co.) in 1876 and 1877.
He was a member of the New York State Senate (27th D.) in 1882 and 1883.