Act of Spiritual Communion

When Should You Make an Act of Spiritual Communion?

The most common occasion for making an Act of Spiritual Communion is when we cannot fulfill our obligation to attend Mass on a Sunday or Holy Day of Obligation, whether because of illness or bad weather, or some other reason outside of our control. It is also good to make an Act of Spiritual Communion when we can attend Mass, but when something prevents us from receiving sacramental Communion that day—say, a mortal sin that we know we have not had the opportunity to confess yet.
But our Acts of Spiritual Communion do not need to be confined to those times. In an ideal world, it would be best to attend Mass and receive Communion every day, but we can't always do so. We can, however, always take 30 seconds or so to make an Act of Spiritual Communion. We can even do so multiple times a day—even on days when we have been able to receive the Eucharist. Why would we do that? Because each Act of Spiritual Communion that we make increases our desire to receive sacramental Communion, and also helps us to avoid the sins that would make us unable to receive Communion worthily.

ThoughtCo. "An Act of Spiritual Communion." Learn Religions, Feb. 11, 2020, learnreligions.com/an-act-of-spiritual-communion-a-daily-catholic-prayer-542748.