Hindu festivals tied to Purnima are set by the tithi, the lunar day in the panchang, and not by the minute of the astronomical full moon. A panchang day also runs from sunrise to sunrise, so a festival can sit a day away from the full moon, and dates differ between regions and traditions. In 2027 a standard panchang calculated for New Delhi places Sharad Purnima on Thursday 14 October, while the full moon comes at 19:17 IST on 15 October. The same panchang puts Magha Purnima on 20 February, before the full moon at 04:54 IST on 21 February. Holi varies too: that panchang gives Rangwali Holi on 22 March, while the central government holiday list for Delhi marks Holi on 23 March. Always check the panchang used in your family or temple.
According to that New Delhi panchang, the other major Purnima observances of 2027 fall as follows, and a regional calendar may shift them by a day. Buddha Purnima, which marks the birth of the Buddha, is on Thursday 20 May, also a central government holiday. Guru Purnima, when disciples honour their gurus, is on Sunday 18 July, the same evening as a penumbral lunar eclipse at 21:32 IST. Most Hindu calendars do not list penumbral eclipses, and no sutak applies to them. Raksha Bandhan is on Tuesday 17 August. Kartik Purnima falls on Sunday 14 November, which is also the government holiday for Guru Nanak’s birthday, traditionally celebrated by Sikhs on the full moon of Kartik.