One who chants the holy name of the Lord constantly is guaranteed to return home.

At the time of death one is certainly bewildered because his bodily functions are in disorder. At that time, even one who throughout his life has practiced chanting the holy name of the Lord may not be able to chant the Hare Krishna mantra very distinctly. Nevertheless, such a person receives all the benefits of chanting the holy name. While the body is fit therefore, why should we not chant the holy name of the Lord loudly and distinctly? If one does so, it is quite possible that even at the time of death he will be properly able to chant the holy name of the Lord with love and faith. In conclusion, one who chants the holy name of the Lord constantly is guaranteed to return home, back to Godhead, without a doubt.

Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Sixth Canto, Chapter 02 – Text 49