The 16th Amendment created the federal income tax in 1913

The 16th Amendment to the U.S. Constitution, ratified on February 3, 1913, gave Congress the power to collect income tax from individuals and corporations without apportioning it among the states. Before this amendment, the federal government relied mainly on tariffs and excise taxes. The amendment's straightforward language—"The Congress shall have power to collect taxes on incomes, from whatever source derived, without apportionment among the several States"—removed a legal barrier that had blocked income tax for decades.

This amendment did not create income tax out of nowhere. Congress had tried to impose an income tax during the Civil War, and again in 1894. But in 1895, the Supreme Court ruled in Pollock v. Farmers' Loan & Trust Co. that a direct tax on income from property (like stocks and bonds) was unconstitutional unless it was divided among states based on population. That ruling made a national income tax nearly impossible to collect fairly. The 16th Amendment overturned that decision by explicitly allowing Congress to tax income without that apportionment requirement.

Key Takeaways

  • The 16th Amendment, ratified in 1913, gave Congress the power to collect income tax directly from people and businesses without dividing the tax among states by population.
  • Before 1913, the Supreme Court had blocked income tax as unconstitutional, forcing the federal government to rely on tariffs and other indirect taxes.
  • The amendment was a response to the 1895 Pollock decision, which made a fair national income tax legally impossible under the old rules.
  • The first federal income tax under the 16th Amendment was collected in 1913, starting at a low rate that applied only to the wealthiest Americans.

Why the Supreme Court blocked income tax before 1913

The Constitution divides taxes into two categories: direct taxes and indirect taxes. Indirect taxes—like tariffs on imported goods or excise taxes on specific items—could be collected uniformly across the country. Direct taxes, which included income tax, had to be apportioned among states based on their population. This meant that if the federal government wanted to collect $100 million in income tax, each state would pay a share based on how many people lived there, not on how much income people in that state actually earned.

This apportionment rule made a practical income tax impossible. A state with many poor residents would owe the same total tax as a state with fewer but much wealthier residents. Congress would have had to set wildly different tax rates in different states to collect the same amount from each, which was unworkable. When Congress tried to impose an income tax in 1894, the Supreme Court struck it down in the Pollock case, saying the apportionment rule applied. The only way forward was to change the Constitution itself.

How the amendment was ratified

Ratifying a constitutional amendment requires approval from three-fourths of the states. The 16th Amendment moved quickly compared to most constitutional changes. Congress passed it in July 1909, and by February 1913, enough states had voted to approve it. The amendment had broad support because many people believed the federal government needed a more reliable source of revenue, and because income tax could be designed to fall mainly on wealthy Americans.

The ratification process took about three and a half years, which was relatively fast for a constitutional amendment. Once it was ratified, Congress when ready began writing the first income tax law under this new power. The first federal income tax collected under the 16th Amendment took effect in 1913, with a top rate of 7 percent on the highest earners. At that time, only about 3 percent of Americans earned enough to owe any income tax at all.

What changed after the 16th Amendment passed

Before 1913, the federal government collected most of its money from tariffs—taxes on imported goods. Tariffs made up about half of all federal revenue. Income tax, when it was allowed, was temporary and limited. After the 16th Amendment, income tax became the largest source of federal revenue, and it has remained so ever since. This shift gave the federal government a much larger and more stable source of money.

The amendment also changed how Americans thought about their relationship with the federal government. Income tax is collected directly from workers' paychecks and from business profits, making the federal government's claim on the economy visible in a way tariffs never were. Over the following decades, income tax rates rose, especially during wars and economic crises, and the tax system became more complex. But the basic power granted by the 16th Amendment—to tax income without apportionment—remains the foundation of federal taxation today.

How income tax rates have changed since 1913

The first income tax under the 16th Amendment was very mild. In 1913, the lowest rate was 1 percent, and the highest was 7 percent, but only on income above $500,000 (equivalent to roughly $14 million today). Most Americans paid nothing. The tax was designed to fall on the wealthy, and it did.

Rates climbed sharply during World War I and World War II. By 1944, the top rate reached 94 percent on the highest earners. After the wars, rates fell but remained high by modern standards. In the 1950s and 1960s, the top rate was around 70 percent. Rates dropped significantly in the 1980s and have fluctuated since, depending on which party controlled Congress and the presidency. Today's rates are lower than they were for most of the 20th century, but income tax remains the federal government's largest source of revenue.

The difference between the 16th Amendment and earlier tax attempts

Congress had tried to impose income taxes before the 16th Amendment, most notably during the Civil War (1861–1865) and again in 1894. The Civil War income tax was temporary and widely accepted because the nation was fighting for its survival. The 1894 tax was meant to be permanent, but the Supreme Court struck it down in 1895, ruling that it violated the apportionment rule.

The key difference after 1913 was that income tax no longer needed to follow the apportionment rule. Congress could set one tax rate for the entire country and collect it directly from individuals and businesses. This made income tax practical and fair in a way it had never been before. The 16th Amendment did not invent the idea of income tax—other countries had used it for decades—but it removed the constitutional obstacle that had prevented the United States from using it effectively.

Frequently Asked Questions

Did the 16th Amendment create income tax, or did it just allow it?

The amendment allowed Congress to collect income tax. It did not create the tax itself. Congress had to pass a separate law to actually impose income tax, which it did in 1913. The amendment removed the constitutional barrier that had blocked income tax before.

What would happen if the 16th Amendment were repealed?

If the 16th Amendment were repealed, Congress would lose the power to collect income tax without apportioning it among states. This would make income tax as a major revenue source essentially impossible, just as it was before 1913. The federal government would have to rely on other sources of revenue, such as tariffs, excise taxes, or borrowing.

Why did it take a constitutional amendment instead of just a new law?

The Supreme Court had already ruled in 1895 that income tax violated the Constitution's apportionment rule. A new law would have been struck down by the same court. The only way to overturn that ruling was to amend the Constitution itself, which is what Congress and the states did.

Were there any states that did not ratify the 16th Amendment?

Yes. A few states, mostly in the South, voted against ratification. However, the amendment only needed three-fourths of the states to approve it, so the opposition did not prevent it from becoming part of the Constitution. By 1913, enough states had voted yes to make it official.