Self-transcendence
Self-actualization is experienced when an individual has realized and fulfilled his full potential, his full-self. One of the best attributes of an actualized being is having the ability the accept his own self and others, thus making that person enjoy life and appreciate the beauty of each moment of experience.
While self-transcendence is "beyond self". This is the highest or the holistic level of human consciousness. A person who has reached this level has the ability to see others more important than his own self. This is the level where you are willing to lay down your own life for others. This is achievable only when we focus on things beyond the physical need; spiritual awakening is the key, the unity between the soul, the body and the spirit.
In short, self-actualization deals with the soul and self-transcendence deals with the human spirit.