The official calendar adopted by the Nepalese is the Bikram Sambat (B.S). The Bikram Sambat New Year begins with the month of Baisakh (mid-April). For all religious festival and auspicious personal events and rituals, Nepalese makes use of the lunar calendar. Religion plays a vital role in all festivals in Nepal, whether Hindu or Buddhist. One can see a blend of these two religions in most of the Nepalese Festivals. Nepalese celebrates festivals with great enthusiasm and elan. It is said that hardly a day passes in Nepal without a festival being celebrated somewhere.

Certain festivals are celebrated nationwide, while others are of a local nature, observed within a certain region or community. Based on this, Nepalese festivals can be broadly classified into three categories: those that are celebrated nationwide, regionally or locally, and by the community. Major festivals like Bada Dasain or Durga Puja, Tihar, or Laxmi Puja (Festival of Lights), Buddha Jayanti, or the birthday of Lord Shiva, Janai Purnima, Ram Navi and Krishna Janmasthami are celebrated throughout the country. Some prominent festivals that are celebrated with great fanfare are the Indra Jatra of Kathmandu, Rato Macchindranath Yatra of Patan, Bisket Jatra of Bhaktapur, Ghoda Jatra of Kathmandu, Mange Shankranti, or the first day of the month Magh, Chandeshwari Jatra of Banepa. Pnachok Bhagwati Jatra of Palanchok, Bhagwati Jatra of Palpa, Gosain Kunda Mela at Gosai Kunda in Rasuwa District and Haleshi Mahadev Mela of Khotang.

Similarly, other noteworthy local festivals are the Gatha-Muga, or Gatha Karna, in Kathmandu, Chariot pulling festival of the Kumari in Kathmandu, Bajra Barahi jatra of Tistung in Makwanpur, Janaki Vivaha, or Viva Panchami in Dhanusha, Triveni Mela ta Udayapur, Baraha Chhetra Mela in Sunsari, Mai-Pokarhi Mela in Ilam, Bhimsen jatra in Dolkha and Indreshwar Mela in Panauti. Festivals such as Chhath, Fagu and Holi (Festival of Colors) are celebrated regionally. Nepalese festivals are generally woven around the monsoon-driven agricultural cycle, and with rice being the most important stable crop, many of these festivities are observed after the plantation and harvesting of Paddy. Every Festival involves the worshipping of the concerned deities and then sitting for a feast thereafter. A legend or folklore is behind every festival in Nepal.