How do I find the tithi for my parent's yearly śrāddha?

note the lunar month and tithi on the day of death; the śrāddha falls on that same tithi each year.

The annual śrāddha (varṣika or pratyābdika śrāddha) follows the Hindu lunar calendar, not the English date. Find the month (e.g. Kārtika), the pakṣa (bright or dark half) and the tithi that was current at the time of death. A pañcāṅga, the family priest or Chiluka's /today page can tell you this. Note that the tithi at sunrise and the tithi at the moment of death may differ; families usually follow the tithi current at death, but ask your priest.

Each year, look up when that tithi falls in that month. Because of the lunar calendar, the English date moves by up to a few weeks. In an Adhika-māsa year, priests advise which month to use.

Separately, in Pitṛ Pakṣa you do śrāddha on the same tithi (without regard to month). Write both details in a family notebook so the next generation has them.

Source: Nirṇayasindhu; Dharmasindhu · Keep a family record of death tithis

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