From the end of 1919 her health declined fast. She was getting an intermittent fever, the seriousness of which was not at first recognised. All local treatment was at first tried, but as it had little effect, she was brought to Calcutta in a very emaciated condition. It was diagonised as Kala-Azaar (Black-water Fever) by doctors. There was no effective treatment for it in those days and she succumbed to it on 20th July 1920. Two remarkable happenings have to be recorded in connection with her last days. It has been mentioned that her attachment for Radhu was the main prop for her to sustain her physical life. Now it was noticed that a few days before her demise, she became entirely free from her strong bond of affection for Radhu. She, who could not till then remain in a place without Radhu by her side, now asked her not to come near her. On the other hand she wanted her to go to Jayrambati immediately. When Radhu's infant child went near her, she asked it to be carried away. When disciples and devotees pleaded with her on behalf of Radhu, she openly declared that she had completely taken her mind away from her. For Swami Saradananda and others, who knew the esoteric side of the Mother's personality, it was an indication that she was leaving her physical frame soon.
She was now fast sinking. Five days before her passing, an old devotee named 'Mother of Annapurna' was called into her room. When the lady expressed her fears about the future, the Mother remarked: "Why do you fear? You have seen the Master. But I tell you one thing-if you want peace of mind, do not find fault with others. Rather see your own faults. Learn to make the whole world your own. No one is a stranger. The whole world is your own." Perhaps this embodies her last message to the world also.
During the last three days she practically spoke nothing beyond calling Swami Saradananda to her side and saying: "Sarat, I am going. Yogin, Golap and the rest are here. You look after them."
Just before passing away, her face and body became dark and shrivelled, but to the astonishment of all, a great change took place after life was extinct. Her shrivelled form was found to relax, and her face swelled up and assumed a radiant hue. Her countenance seemed to resemble the face of the image of the Goddess Durga used in worship-mellow and golden in colour, with the expression of calmness and serenity writ large on it. This expression lingered on her face for a long time...