Isaac Chapman Bates (January 23, 1779 – March 16, 1845) was an American politician from Massachusetts.

He was born in Granville, Massachusetts, and graduated from Yale College in 1802.

He was chairman of the U.S. House Committee on Military Pensions in the Twenty-first Congress.

He was elected as a Whig to the United States Senate to fill the vacancy in the term ending March 3, 1841, caused by the resignation of John Davis and on the same day elected for the term commencing March 4, 1841, and served from January 13, 1841, until his death.

He was chairman of the U.S. Senate Committee on Pensions (Twenty-seventh and Twenty-eighth Congresses); interment in Bridge Street Cemetery, Northampton, Massachusetts.