Toshikoshi soba is the Japanese New Year's Eve custom of eating buckwheat noodles for longevity.
The Japanese name means “year-crossing soba.” Families commonly eat the noodles on December 31, either before or around midnight. Their long, thin shape is associated with a long life, while the ease with which soba can be bitten is sometimes linked symbolically with leaving the hardships of the old year behind.
The dish is a custom rather than a single fixed recipe. Toppings and broth vary by region and household, and some people eat it at restaurants or after visiting a temple. The important element is its association with crossing from one year into the next.
Toshikoshi soba is distinct from osechi ryori, the collection of special foods traditionally eaten during the first days of the New Year. It is also separate from mochitsuki, the communal pounding of rice to make rice cakes.