Holy Days of obligation & Feast Days 

In addition to Sunday, the days to be observed as holy days of obligation in the Latin Rite dioceses of the United States of America, in conformity with canon 1246, are noted as follows:

Solemnity of Mary ~ January 1 ~ Holy Day of Obligation

Epiphany ~ January 6 ~ Feast Day

Ash Wednesday ~ Feast Day

Holy Thursday ~ Feast Day

Good Friday ~ Feast Day

Easter Sunday ~  Feast Day

Ascension of Jesus ~ May 29 ~ Holy Day of Obligation

Pentecost ~ Feast Day

Corpus Cristi ~ Feast Day

Assumption of Mary ~ August 15 ~ Holy Day of Obligation

All Saints' Day ~ November 1 ~ Holy Day of Obligation

Immaculate Conception of Mary ~ December 8 ~ Holy Day of Obligation

Christmas ~ December 25 ~ Holy Day of Obligation

Holy days of obligation are feast days on which Catholics are required to attend Mass and to avoid (to the extent that they are able) servile work. The observance of the Holy Days of Obligation is part of the Sunday Duty, the first of the Precepts of the Church. 

*** Whenever January 1 , the solemnity of Mary, Mother of God, or August 15 , the solemnity of the Assumption, or November 1 , the solemnity of All Saints, falls on a Saturday or on a Monday, the precept to attend Mass is abrogated. ***