At the beginning of every Mass, a pronouncement of absolution is added to complete the Penitential Rite.  The absolution received does forgive all earthly sin provided the person receiving this absolution is sorry for their sins and does desire to be forgiven.  No private confession is necessary to achieve the desired forgiveness of sins beyond the absolution received at Mass.

Lastly, individual confession is always available to those who desire it.  It is usually reserved for individuals who have had an ongoing problem in their relationship with God and desire to receive helpful advice in the living out of their Christian faith.