In the Catholic Church, Holy Days of Obligation (also called holydays, holidays, or days of obligation) are days on which "the faithful are to refrain from engaging in work or activities that hinder the worship owed to God, the joy proper to the Lord's Day, the performance of the works of mercy, and the appropriate relaxation of mind and body. Family needs or important social service can legitimately excuse from the obligation of Sunday rest. 
The faithful should see to it that legitimate excuses do not lead to habits prejudicial to religion, family life, and health"
Catechism of the Catholic Church 2185

January 1: The Feast of Mary, the Holy Mother of God
This is not a Holy Day of Obligation
Masses:

• Friday, Dec. 31, 2021 at 5:00pm (vigil) 
• Saturday, Jan. 1, 2022 at 9:00am 

Thursday, May 21: Ascension of the Lord 
This IS a Holy Day of Obligation
(40 days after Easter Sunday)

Tuesday, August 15: Assumption of the Blessed Virgin Mary
This IS a Holy Day of Obligation
Masses:

• Vigil Mass on Monday, August 14 at 6:30pm
• Tuesday, August 15 at 8:30am and 6:30pm

Wednesday, November 1: All Saints' Day
This IS a Holy Day of Obligation
Masses:

• Tuesday, October 31st Vigil Mass at 6:30pm
• Wednesday, November 1 at 8:30am and 6:30pm

Friday, December 8: The Solemnity of the Immaculate Conception
This IS a Holy Day of Obligation
Masses:

• Vigil Mass on Thursday, December 7 at 6:30pm
• Friday, December 8 at 8:30am and 6:30pm

Monday, December 25:  The Navity of the Lord (Christmas)
This IS a Holy Day of Obligation

Mass times will be added.

Monday, January 1, 2024 :  Solemnity of Mary, the Holy Mother of God
This is NOT a Holy Day of Obligation

Mass times will be added.