In Italy's New Year's Eve tradition, red underwear is commonly worn to attract luck.
The custom is associated with wishes for good fortune, love, vitality, and prosperity in the coming year. People may wear red garments beneath their ordinary clothing, making the practice a private ritual even when the public celebration involves dinners, fireworks, and midnight toasts.
In some versions of the custom, the underwear should be new, and some people say it should be received as a gift. These details are not universal rules, however; the color itself is the most recognizable part of the tradition.
Red has long carried associations with passion and celebration in Italian and wider European culture. The practice should not be confused with Brazil's widespread white clothing tradition or with Spain's midnight grape ritual. Customs can vary by region and family, but red is the standard answer for the Italian New Year's Eve superstition.