Pongal, as all Indian festivals, have interesting legends attached to it. Originated as a Dravidian harvest festival, it has found no mention in Indo-Aryan Puranas. According to the popular legend, the first day of the festival known as Bhogi Pongal was once dedicated to Lord Indra. The child Krishna came to know of the pride and arrogance of Indra on being the king of the deities and that he thought himself to be the most powerful of all the beings. He conjured a plan to teach him a lesson. When, as usual, his father an other villagers who were cowherds by profession, were preparing for the festival and offerings to Indra, Krishna objected and persuaded them to worship Mt Govardhan instead, as it gave them fodder for their cattle. When Indra came to know of this, he considered it a heresy of the villagers and sent thunderous pours, storms and lightning to drown them and punish them.

However, Lord Krishna had other plans in mind and he lifted up the Govardhan mountain on his little finger to protect the cowherds and their cattle. The simpletons tried to help him by putting their own sticks in the mountain out of love. The rains continued for three days and at last Indra realized his mistake and divine power of the young boy. He promised humility and begged Krishna's forgiveness. Since then, Krishna allowed to let the Bhogi celebrations continue in honor of Indra. A beautiful depiction of the scene can be scene at Mahabalipuram where Krishna lifting Govardhan has been carved skilfully and since then the origin of the festival of Pongal came into being.

Another legend associated to the third day of Pongal known as Mattu Pongal involves Lord Shiva and his mount, Nandi the bull. It is said that once Shiva ordered Nandi to go to the Earth and deliver his message to the people that they should take oil bath every day and eat food once a month. However, the dozing Nandi could not hear the message right and told the people to eat everyday and take oil bath once a month. Shiva was furious and said that due to his folly, there will be lack of grains on the Earth and so he would have to remain on Earth to help humans plough the fields. Mattu Pongal is also known as Kanu Pongal and is in many ways resemble the festivals of Raksha Bandhan and Bhai Dooj of North India as women pray for welfare of their brothers on this day.