Ōmisoka is the Japanese name for New Year's Eve, observed immediately before the Shōgatsu New Year period.
It is one of the most important annual observances in Japan. Families commonly clean their homes, settle unfinished business, prepare holiday foods, and spend the evening together. Many people eat soba noodles called toshikoshi soba, whose name means “year-crossing noodles.”
At midnight, Buddhist temples perform Joya no kane, ringing bells 108 times. On New Year's Day and the days that follow, people participate in hatsumōde, the first shrine or temple visit of the year, and exchange the greeting akemashite omedetō gozaimasu.
Ōmisoka should not be confused with Shōgatsu. Ōmisoka specifically means New Year's Eve, while Shōgatsu refers to the New Year season, especially the first days of January. The Japanese New Year calendar was aligned with January 1 after Japan adopted the Gregorian calendar in 1873.