Pathar Chauth is observed on the fourth day of the waxing phase of moon (Shukla Paksha) in the month of Bhadrapad month. In 2017, the date of Pathar Chauth is August 25. Pathar Chath is observed on the day of Ganesh Chaturthi festival. One should not look at the moon on the day and the moon on Vinayaka Chaturthi day is known as Pathar Chauth Moon.
One of the popular legends associated with Pathar Chauth is that if one sees moon on Ganesh Chaturthi day it will bring bad luck. To avoid the bad luck, people throw stones on one’s own house and use abusive words. This tradition is also known as Pathar Chauth.
In some North Indian regions, there is a belief that Lord Shiva as an answer to the prayers of his devotees killed demons that were creating havoc on earth on the day.
There are numerous different reasons for observing Pathar Chauth and it varies from region to region.