Patriots' Day is an official state holiday observed on the third Monday in April in both Massachusetts and Maine. Consequently, its specific calendar date changes each year, rather than being fixed to a single numerical date.
The holiday commemorates the anniversary of the Battles of Lexington and Concord, which occurred on April 19, 1775, marking the start of the American Revolutionary War. The observance was originally fixed to April 19th. However, in 1969, legislation in Massachusetts moved the holiday to the third Monday of the month. This change aligned with a broader trend of creating three-day weekends for public holidays. The day is also intrinsically linked with the Boston Marathon, which has been held on this holiday since 1897.
To determine the date for any given year, one must identify the third Monday of that specific April. For example, the holiday falls on April 15 in 2024, April 21 in 2025, and April 20 in 2026. This floating schedule is a direct result of the modern legislative practice of tying certain holidays to a specific day of the week.
