When do the laws of Yahrzeit apply: on the date of death or burial

Is the Yahrzeit calculated on the day of death or the day of burial?

The Yahrzeit is counted on the day of death, not on the day of burial. However, in the first year, one must continue the mourning practices for the entire twelve months from the burial.

It is written in the Shulchan Aruch, Orach Chaim, Siman 668, Se'if 8: "One only needs to fast on the day of his father's death, not on the day of burial." And in the Rema, Siman 572, Se'if 12, it is written: "One fasts on the day of death, not on the day of burial (Mahari"v Siman 121 and Mahara"i Siman 296/293 and the later authorities), unless one was present at the burial but not at the death." In the Levush, it is written: "It is customary to fast on the day one's father or mother died, and I heard the reason is to repent due to the danger, as one's fortune is diminished on this day when his father or mother died. According to this reason, it seems to me that one fasts on the day of death, not on the day of burial, whether he was present at the death or not, and not as my teacher, of blessed memory, concluded his words, unless one was present at the burial but not at the death, which makes no difference, so it seems to me." In the Taz, Siman 572, Se'if Katan 9, it is written in the name of the Masa'at Binyamin, Siman 84, that this is specifically in the second year, but in the first year, when mourning begins from the burial, therefore the year ends with the burial, and thus one fasts on the day of burial. The Taz wrote about this: "And I do not believe that these words came from the mouth of that righteous person, for surely no one counts twelve months except from the day of death, for if someone did not hear that his father died until half a year later, surely he would not count only half a year in mourning, as it is written in Siman 394 that the entire year the law is strict, etc., this is from the death of the deceased, not from the beginning of mourning, etc." And he concluded that even in the first year, one counts from the day of death. However, in the Nekudot HaKesef, Siman 572, Se'if 12, it is written: "The judgment of the wicked begins from the day of burial, and therefore mourning begins only from the day of burial, and even if one was not buried until several weeks later, mourning begins only from the day of burial, as above in Siman 375. And if so, when he begins to mourn on the first day, he must also stop mourning on the first day, for he must mourn all twelve months, which are his days of judgment, that is, from the day of burial. And this is clear:" and his intention is as the Masa'at Binyamin wrote, that there is a distinction between the first year and the second year. In the first year, the Yahrzeit is on the day of burial, and in the second year, the Yahrzeit is on the day of death. In the Shach, there, Se'if Katan 10, it is written: "Therefore, it seems that one should always fast on the day of death, but if the day of death is distant from the day of burial by three or four days or more, one should fast in the first year on the day of burial to make the Yahrzeit at the completion of mourning, since it is not possible otherwise, and also because it is an uncommon event, one can rely in such a case on the opinion to do it on the day of burial, and from the first year onward, one fasts on the day of death, but if one's father died and was buried on the same day or the next day, one should fast on the day of death even in the first year, as it seems to me, and examine this:" And in the words of the Shach, there is a slight contradiction from the beginning of his words to the end of his words, as at first he wrote that if there are three or four days, one makes the Yahrzeit on the day of burial, implying that two days are done on the day of death, and the reason is because three days are uncommon, and at the end of his words, it implies that specifically on one day it is done on the day of death, but on two days it is done on the day of burial, and the reason is because the laws begin from the day of burial, and practically from the words of the Pitchei Teshuva, Se'if Katan 3, it seems that the main reason is because of the laws of mourning, and therefore even in two days, the Yahrzeit is done on the day of burial. And so we find four opinions on this. 1. The opinion of the Taz that one always counts from the day of death. 2. The opinion of the Rema that there is a distinction if one was at the burial or not. 3. The opinion of the Masa'at Binyamin that in the first year, one counts from the day of burial, and in the second year from the day of death. 4. The opinion of the Shach that there is a distinction whether there is one day or two days between the day of death and burial. In the Mishnah Berurah, Siman 668, Se'if Katan 44, two opinions are brought and no decision is made, but in the Biur Halacha, Siman 132, in the article Kadishin, a decision is made on the Yahrzeit on the day of death, and here are his words: "The Yahrzeit is counted from the day of death, as written in Yoreh De'ah, Siman 572, Se'if 12, in the gloss regarding fasts. And there is no distinction whether one was at the death or only at the burial, as written in the Levush there, and even in the first year."