The Revenue Act of 1913, also known as the Tariff Act, the Underwood Tariff, the Underwood Act, the Underwood Tariff Act, or the Underwood-Simmons Act re-imposed the federal income tax after 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.