Patriots' Day is not a federal holiday in the United States. It is a state holiday, officially recognized and observed only in Massachusetts, Maine, and as a public school observance in Wisconsin. Its status as a state-level, rather than national, commemoration means it is not a day off for federal employees.
The distinction lies in the designating authority. Federal holidays are those established by the U.S. Congress through federal law, applying to federal institutions and employees nationwide. Patriots' Day, observed on the third Monday in April, was established by state legislatures to commemorate the anniversary of the Battles of Lexington and Concord, the first armed conflicts of the American Revolutionary War in 1775. Because its recognition is at the state level, it does not meet the criteria for a federal holiday.
Consequently, federal government functions, including the U.S. Postal Service, federal courts, and federal agency offices, operate on their normal schedules on Patriots' Day, even within the states that observe the holiday. However, in Massachusetts and Maine, state and municipal government offices, schools, and many businesses are closed. This demonstrates the practical application of federalism, where states retain the authority to create their own public observances separate from those recognized by the national government.
