In the United States, Tax Day is the day on which individual income tax returns are due to be submitted to the federal government.^[3] Since 1955, Tax Day has typically fallen on or just after April 15. Tax Day was first introduced in 1913, when the Sixteenth Amendment was ratified.

The date is delayed if it conflicts with a weekend or public holiday such as Emancipation Day. Natural disasters or public health emergencies, most recently the COVID-19 pandemic, also delay Tax Day when they prevent filing taxes on time, and state income agencies often delay their own submission deadlines to remain in common with that of the federal government. The federal government may set a different deadline for certain states, as it did when Patriots’ Day conflicted.