Nag Panchami in Bengal is observed on Shukla Paksha Panchami in Shraban Month in Bengali calendar. In 2012, Nag Panchami date is 8 July 2012, today, in Bengal. Usually, Nag Panchami Manasa Puja & Ashtanag Puja is observed for more than four times in Aashar month and Shravan month in Bengal. Goddess Manasa Devi and Ashtanag Devtas are worshipped on Nag Panchami Puja.
Nag Panchami in North India and other places of India (except Gujarat) date is July 23, 2012. In Gujarat it is observed 15 days later.