A girl pours water at revelers during Myanmar New Year Thingyan Water Festival in Yangon, Myanmar. *Photo from Wikipedia
The traditional New Year in many South and Southeast Asian cultures is based on the sun’s entry into the constellation Aries. In modern times, it is usually reckoned around 14 April.
The specific New Year observations include:
South Asia
Bohag Bihu (India), Pana Sankranti (India), Sangken (India), Vishu (India), Bisket Jatra (Nepal), Maithili New Year (India and Nepal), Pahela Baishakh or Bengali New Year (Bangladesh and India), Puthandu or Tamil New Year (India, Sri Lanka and so on), Sinhalese New Year (Sri Lanka), Vaisakhi or Sikh New Year (India and Pakistan)
Southeast Asia
Cambodian New Year, Songkran (Laos and Thailand), Thingyan (Myanmar)
East Asia
Water-Sprinkling Festival (Celebrated by the Dai people in Sipsong Panna in the extreme south of Yunnan, China)
*Reference: Wikipedia