Question: What is the proper date of the first yahrzeit, the date of death or the date of burial?
Short Answer: The Mishnah B’rurah rules that the yahrzeit is observed on the date of death in all years. However, many poskim, including Rav Moshe Feinstein zt”l, disagree and rule that where the date of burial is three (or possibly, even two) days after the date of death, the first yahrzeit is observed on the date of burial and all subsequent yahrzeits are observed on the date of death.