Federal income tax was introduced with the Revenue Act of 1861 to help fund the Civil War.

That Act stipulated that income tax “shall be due and payable on or before the thirtieth day of June“.

There is an unsubstantiated claim that the first income tax was paid only by the very wealthy, and they tended to spend their summers vacationing. The Commissioner of Internal Revenue is said to have argued, “The collection of taxes would be much easier if an earlier assessment was made, before they leave town.”

The case of Pollock v. Farmers’ Loan & Trust Co. challenged the constitutionality of the Wilson-Gorman Tariff Act of 1894 which taxed incomes over $4,000 at the rate of two percent. The case was decided by the United States Supreme Court in 1895. The Supreme Court decided that the Act’s unapportioned income taxes on interest, dividends, and rents were effectively direct taxes. The Act was therefore unconstitutional because it violated the Constitution’s rule that direct taxes be apportioned.

In 1913, eighteen years later, the Sixteenth Amendment to the United States Constitution was ratified. This Amendment gave the United States Congress the legal authority to tax all incomes without regard to the apportionment requirement.

The filing deadline for individuals was March 1 in 1913 and was changed to March 15 in 1918 and again to April 15 in 1955.

Today, the filing deadline for U.S. federal income tax returns for individuals remains April 15 or, in the event that the 15th falls on a Saturday, Sunday or holiday, the first succeeding day that is not a Saturday, Sunday or holiday.

Tax Day occasionally falls on Patriots’ Day, a civic holiday in the Commonwealth of Massachusetts and state of Maine, or the preceding weekend. When this occurs the tax deadline is extended by a day for the residents of Maine, Maryland, Massachusetts, New Hampshire, New York, Vermont, and the District of Columbia.

* This is because the IRS processing center for these areas is located in Andover, Massachusetts.

In 2007, Tax Day was on Tuesday, April 17, 2007 because April 15 fell on a Sunday and Monday, April 16 was Emancipation Day, a legal holiday in the District of Columbia.