Solemnity of Mary, Mother of God
Wednesday, January 1st, 2020
Obligatory in 2020:  YES

Ascension of Jesus
Thursday, May 21st, 2020
Obligatory in 2020:  YES

Assumption of the Blessed Virgin Mary
Saturday, August 15th, 2020
Obligatory in 2020:  NO

All Saints' Day
Sunday, November 1st, 2020
Obligatory in 2020:  YES

The Immaculate Conception of the Blessed Virgin Mary
Tuesday, December 8th, 2020
Obligatory for 2020:  YES

Christmas
Friday, December 25th, 2020
Obligatory in 2020:  YES
 

Notes

The number of Days of Obligation vary from year to year, because the precept to attend Mass is lifted (abrogated) if any of the following days:

• 1 January (Solemnity of Mary, Mother of God),
• 15 August (Feast of the Assumption),
• 1 November (Solemnity of All Saints)

falls on a Saturday or on a Monday. The faithful, however, are encouraged to attend Mass on those days. This was decided by the National Conference of Catholic Bishops of the United States of America on December 13, 1991 (Canon 1246) and is effective as of January 1, 1993.

Ascension Thursday is a Holy Day of Obligation in the entirety of the following States: Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, and Nebraska.

In Hawaii since 1992 the only observed Days of Holy Obligation (except Sundays) are Feast of the Immaculate Conception and Christmas.