Reformation Day in Chile is a national holiday that is celebrated on the last Friday in October. The holiday commemorates the Protestant Reformation which began in the 16th century. The day is a tribute to the Protestant Church and its history, and it recognizes the substantial influence of these religious societies in shaping the evolution of European and South American societies. The holiday was first noted in 2008 and officially became a public holiday in Chile from 2009.

The day is known as 'Dia de las Iglesias Evangélicas y Protestantes' in Spanish, which translates to 'Day of the Evangelical and Protestant Churches.' It is the only public holiday in the world apart from Germany that specifically recognises the Protestant Reformation. On this day, people of Chile enjoy traditional celebrations, religious processions and other communal events. Many Catholic churches also hold special masses on this day.

The establishment of Reformation Day as a public holiday in Chile also marked the recognition of the country's substantial Protestant population. It also serves to draw attention to the need for religious unity and acceptance of diverse beliefs within the country. Even though this holiday tends to be religious in nature, it is widely recognized and observed by the majority of the Chilean population regardless of their religious affiliation.