In the Roman Catholic Church, the Holy Days of Obligation are the days, other than Sundays, on which the faithful are required to attend Mass. The 1983 Code of Canon Law standardized ten days to be observed as Holy Days of Obligation throughout the Church. These days are:
- The Immaculate Conception (December 8)
- Christmas (December 25)
- Mary, the Mother of God (January 1)
- Epiphany (January 6)
- St. Joseph (March 19)
- St. Peter and St. Paul (June 29)
- The Assumption of Mary (August 15)
- All Saints (November 1)
- The Ascension (40 days after Easter)
- Corpus Christi (60 days after Easter)