प्राचीन समय की बात है कि एक बार एक गांव में एक गरीब ब्राह्मण रहता था। वह ब्राह्मण नियमित रुप से श्री विष्णु का पूजन किया करता था। उसकी पूजा-भक्ति से प्रसन्न होकर उसे भगवान श्री विष्णु ने दर्शन दिये और ब्राह्मण से अपनी मनोकामना मांगने के लिए कहा। ब्राह्मण ने लक्ष्मी जी का निवास अपने घर में होने की इच्छा जाहिर की। यह सुनकर श्री विष्णु जी ने लक्ष्मी जी की प्राप्ति का मार्ग ब्राह्मण को बता दिया। जिसमें श्री हरि ने बताया कि मंदिर के सामने एक स्त्री आती है जो यहां आकर उपले थापती है। तुम उसे अपने घर आने का आमंत्रण देना और वह स्त्री ही देवी लक्ष्मी है। देवी लक्ष्मी जी के तुम्हारे घर आने के बाद तुम्हारा घर धन और धान्य से भर जाएगा। यह कहकर श्री विष्णु चले गए. अगले दिन वह सुबह चार बजे ही मंदिर के सामने बैठ गया। लक्ष्मी जी उपले थापने के लिए आईं तो ब्राह्मण ने उनसे अपने घर आने का निवेदन किया। ब्राह्मण की बात सुनकर लक्ष्मी जी समझ गई कि यह सब विष्णु जी के कहने से हुआ है। लक्ष्मी जी ने ब्राह्मण से कहा की तुम महालक्ष्मी व्रत करो, 16 दिनों तक व्रत करने और सोलहवें दिन रात्रि को चन्द्रमा को अर्ध्य देने से तुम्हारा मनोरथ पूरा होगा। ब्राह्मण ने देवी के कहे अनुसार व्रत और पूजन किया और देवी को उत्तर दिशा की ओर मुंह करके पुकारा, लक्ष्मी जी ने अपना वचन पूरा किया। उस दिन से यह व्रत इस दिन विधि‍-विधान से करने व्यक्ति की मनोकामना पूरी होती है।

Among the many stories associated with this vrat, two related to the Mahabharata are very popular. Once, when Vedvyasa, the author of the ancient Indian epic visited Hastinapur, the kingdom of visually-impaired king Dhritarashtra, Queen Gandhari and Kunti, sought his blessings. They wanted to know how they could ensure their kingdom remains wealthy and prosperous. To answer their question, the sage said that they must keep a vart of Mahalakshmi for sixteen consecutive days.

He revealed that the fasting period must begin on the Ashtami Tithi of Bhadrapada month, Shukla Paksha (bright phase of the Lunar cycle) and end on the Ashtami Tithi of Ashwin, Krishna Paksha (dark period of the Lunar cycle).

Gandhari kept a vrat and invited all the women in the kingdom but did not send an invite to Kunti. And when Arjuna learnt about it, he asked his mother (Kunti) to start making preparations for the vrat. He went to the Deva Loka and asked his spiritual father, Indra, to send his elephant, Airavat to the Prithvi Loka for a few days. The Gajalakshmi avatar (Lakshmi with elephants on either side) of Goddess Lakshmi represents power, prosperity, good luck and bounty. Thus, by bringing Airavat for his mother as she observed the Mahalakshmi Vrat, Arjuna helped in performing the vrat without hindrances.

According to the other story associated with this vrat, Yudhishthira wondered how he could get his lost wealth and kingdom back after losing the game of Chausar against Duryodhana. Therefore, he sought help from Lord Krishna, who then asked him to observe the Mahalakshmi Vrat.

And as per another story, there lived a poor Brahmin, who happened to be a great devotee of Lord Vishnu. Pleased by his devotion, Lord Vishnu once appeared before him and asked him to wish for a boon. The poor Brahmin expressed his desire for hosting Goddes Mahalakshmi at his humble abode. And Lord Vishnu fulfilled granted him by saying that the Goddess would soon visit him. Subsequently, the Brahmin waited for the Goddess to arrive, and after seeing her, he did not want to let her go from his humble abode. He wanted the Mother Goddess to stay back, and therefore, Devi Lakshmi asked him to perform the Mahalakshmi vrat. She said that she would always remain in his house. The Brahmin sincerely followed her instructions and soon became wealthy after keeping the vrat.