When Was the 16th Amendment Ratified and How It Passed

The 16th Amendment was ratified on February 3, 1913, when the 36th of the then-48 states approved it, giving Congress the constitutional power to tax income from any source without apportioning the tax among the states by population. Secretary of State Philander Knox certified the ratification on February 25, 1913, and the amendment became a permanent part of the Constitution on that date as a matter of official record.¹

Why an Amendment Was Needed

Congress had briefly imposed an income tax during and after the Civil War, but the Supreme Court closed that door in 1895. In Pollock v. Farmers’ Loan & Trust Co., the Court held that taxes on income from real estate and personal property were “direct taxes” that the Constitution required to be divided among the states according to population.² Splitting an income tax by state population rather than by what people actually earned made the tax unworkable, and for nearly two decades the federal government relied on tariffs and excise taxes instead.

By 1909, the political pressure to fix that had built up. On June 16 of that year, President William Howard Taft sent a message to Congress recommending a constitutional amendment rather than another statute the Court would likely strike down. Taft called the taxing power one that “might be indispensable to the nation’s life in great crises” and treated the amendment route as the “much wiser policy.”³

How Congress Sent It to the States

The 61st Congress moved fast. Senate Joint Resolution 40 proposed the amendment during the first session in 1909.⁴ The Senate passed it unanimously; the House approved it with only 14 votes against. Both chambers acted in July 1909, well clear of the two-thirds threshold that Article V requires before an amendment can go to the states.⁵ Some conservatives who voted yes reportedly expected the states to kill the amendment, and were surprised by what followed.⁶

The proposed text was a single sentence: “The Congress shall have power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration.”⁶ Those 30 words removed both barriers Pollock had put in place.

The State Ratification Timeline

With 48 states in the Union, three-fourths meant 36 approvals were needed.⁷ Alabama went first, ratifying on August 10, 1909, roughly a month after Congress finished its work.

Progress was slow through the rest of 1909 and into 1910 as legislatures weighed the economic implications. Kentucky and South Carolina came in during early 1910, followed by several southern and border states. The pace picked up sharply in 1911. In January and February of that year, more than a dozen states ratified, including Ohio, California, Michigan, and Iowa. New York ratified in July 1911. By the end of 1911, 30 states had signed on.

Arizona, Minnesota, and Louisiana ratified during 1912. West Virginia ratified on January 31, 1913, bringing the total to 35, one short of the constitutional threshold.

February 3, 1913: The Threshold Is Reached

Three states ratified on the same day, February 3, 1913: Delaware, Wyoming, and New Mexico. Their combined action pushed the count past 36 and completed ratification. Because all three acted on the same date, the record does not identify a single “36th” state. From Alabama’s first approval to that final day, the process took about three and a half years.

Several states ratified after the threshold had already been crossed. New Jersey followed on February 4, Vermont on February 19, Massachusetts on March 4, and New Hampshire on March 7, the last of which had rejected the amendment in 1911 before reversing itself.⁸ In all, 42 of the 48 states eventually ratified.

February 25, 1913: Official Certification

The constitutional requirements were satisfied on February 3, but the amendment still needed formal certification. That job fell to Secretary of State Philander Knox. Several states had submitted ratification documents with small wording variations, using “sources” instead of “source,” “levy” instead of “lay,” or “income” instead of “incomes,” along with differences in capitalization and punctuation.⁹

A February 15, 1913 memorandum from the Office of the Solicitor concluded that the errors were “merely typographical and incidental to an attempt to make an accurate quotation,” and that each legislature clearly intended to ratify the amendment Congress had proposed. The memo noted that similar variations had appeared in state resolutions for the 14th and 15th Amendments without affecting their validity.⁹ On February 25, 1913, Knox issued his proclamation certifying that the 16th Amendment had been validly ratified and was part of the Constitution.¹

The States That Did Not Ratify

Three states formally rejected the amendment and never reversed course: Connecticut, Rhode Island, and Utah.⁷ Three others, Florida, Pennsylvania, and Virginia, never took a formal vote at all. With 42 states ratifying, the holdouts did not affect the outcome.

What Ratification Made Possible

Congress used its new authority within months. On October 3, 1913, President Woodrow Wilson signed the Revenue Act of 1913, also called the Underwood-Simmons Act, creating the first permanent federal income tax. The base rate was 1 percent on net income above $3,000 for single filers and $4,000 for married couples, with a top surtax of 6 percent on incomes above $500,000.¹⁰

The first Form 1040 appeared that year, covering income earned from March 1 through December 31, 1913.¹¹ Because of the high exemption thresholds, fewer than 1 percent of Americans actually owed income tax in that first year.⁶

1
The American Presidency Project. Proclamation by Secretary of State Philander C. Knox – Ratification of the Sixteenth Amendment to the Constitution Authorizing Congress to Lay and Collect Income Taxes
2
Justia. Pollock v. Farmers’ Loan and Trust Co., 157 U.S. 429 (1895)
3
The American Presidency Project. Message to the Congress Concerning Tax on Net Income of Corporations
4
U.S. Capitol – Visitor Center. S.J. Res. 40, Joint Resolution Proposing an Amendment to the Constitution of the United States, June 28, 1909
5
Constitution Annotated. ArtV.1 Overview of Article V, Amending the Constitution
6
National Archives. 16th Amendment to the U.S. Constitution: Federal Income Tax (1913)
7
Constitution Annotated. Intro.6.5 Early Twentieth Century Amendments (Sixteenth Through Twenty-Second Amendments)
8
GovInfo. Amendment XVI – The Congress Shall Have Power to Lay and Collect Taxes on Incomes
9
Justia Case Law. United States v. House
10
Internal Revenue Service. Historical Highlights of the IRS
11
Internal Revenue Service. Form 1040 – Income Tax – Return of Net Income of Individuals (1913)