The previous Halacha mentioned that fortunate occurrences that do not deviate from the normal course of nature are not considered miracles for the purpose of reciting the blessing of “She’asa Li Nes Bemakom Ze” with Hashem’s Name. Nevertheless, if one experiences anything that one would personally classify as a miracle, whether supernatural or something that fits in the normal course of nature, one should hold a Seudat Hoda’a, a meal of gratitude. Rabbi Yair Bachrach (Havot Yair) writes that such a meal has the status of a Seudat Mitzvah. The Mishna Berura (O.H. 218:32) adds that on the anniversary of the miracle, one should give charity specifically to those who study Torah, and should consider it in place of the Korban Toda (lit. Thanksgiving Offering) and one should even read the Torah portion dealing with this offering. Furthermore, he says that one should donate money for one’s city’s communal needs or public works.
The Kaf HaHaim (O.H., § 39), citing the Zohar, explains that one has an obligation to publicize the miracle that one experienced annually, on the anniversary of the occurrence. By doing so on Earth, the angels join in publicizing the miracle in the Heavens and Hashem’s Name becomes exalted. The Kaf Haim (O.H. 218:9) also writes that there if a particular community experienced a salvation from a communal calamity, there is a custom not to recite Tahanun on the anniversary of the day of the miracle.
Summary: One should hold a Seudat Hoda’a if one experienced a personal miracle, and one should give money to charity. It is also important to publicize this miracle annually.