Feast of the Immaculate Conception is not a public holiday. Businesses have normal opening hours.

Many churches hold special masses dedicated to Mary and her conception. It is a particularly special event in the town of San Juan de los Lagos in northeastern Jalisco, central Mexico. Celebrations include street festivals, food stalls, music, exhibitions, and games.

Many theologians, including St Thomas Aquinas, questioned the idea of Mary’s immaculate conception until Pope Pius IX proclaimed it to be an essential dogma in the Catholic Church on December 8, 1854. The written document on this is known as the Ineffabilis Deus. Since then, the Feast of the Immaculate Conception celebrates the belief that Mary was born without sin and that God chose her to be Jesus’ mother.