Bhishma Panchaka Vrata is observed during the last five days of the waxing phase of moon (Shukla Paksha) of Kartik month. The Vrata gets it name from Bhishma of Mahabharata as it was he observed it first after hearing about it from Lord Krishna. The fast should begin by remembering Bhismadeva on the Kartik Suddha Ekadasi day and should end on Purnima. This is not a compulsory vratha like Ekadashi. Observing this Vrata is believed to bring health, wealth and luck. Those who do not have children also perform it for getting children. Some people perform it for redemption of sins.