The United States Revenue Act of 1913 also known as the Tariff Act, Underwood Tariff, Underwood Act, Underwood Tariff Act, or Underwood-Simmons Act (ch. 16, , October 3, 1913), re-imposed the federal income tax following the ratification of the Sixteenth Amendment and lowered basic tariff rates from 40% to 25%, well below the Payne-Aldrich Tariff Act of 1909. It was signed into law by President Woodrow Wilson on October 3, 1913, and was sponsored by Alabama Representative Oscar Underwood.