Question: Why do Parishes Offer Special Masses like Thanksgiving and Memorial Day, even though they’re not Holy Days of Obligation? Am I obligated to attend?

Answer: Out of respect for the various civil celebrations that take place during the year, many dioceses and parishes will host special Masses. However, while it always worthwhile to come together to worship as a community, Catholics are not obligated to attend these celebrations. As the Catechism of the Catholic Church notes, the only times that we are obligated to participate in celebrations of the Eucharist are on Sundays and holy days of obligation:

The first precept (“You shall attend Mass on Sundays and holy days of obligation and rest from servile labor”) requires the faithful to sanctify the day commemorating the Resurrection of the Lord as well as the principal liturgical feasts honoring the mysteries of the Lord, the Blessed Virgin Mary, and the saints; in the first place, by participating in the Eucharistic celebration, in which the Christian community is gathered, and by resting from those works and activities which could impede such a sanctification of these days.