Nagula Panchami during karthika masam is observed on the fifth day, Panchami, in Shukla Paksham of kartika masam. In 2017, Kartika Nagula Panchami date is October 25.
In most of the places, Nagula Panchami, also known as Naga Panchami, is observered during Shravana masam but in some places it is also observed in kartika masam.
Shukla paksha Chavithi, Panchami and Shashti during Kartik month are known as Nagula Chavithi, Naga Panchami and Naga Shashti. During these three days, Serpent Gods or Snake Gods are worshipped.
On Naga Panchami, the day after Nagula Chavithi, women break the fast and worship Naga Puja udyapana. Naga Puja or Valmika Puja is the most observed ritual during these three days dedicated to Naga devatas.