Red underwear is the Italian New Year's Eve tradition associated with good luck, love, and prosperity.
In Italy, wearing something red during the New Year period is widely described as a folk custom, especially when the garment is new and received as a gift. The practice is commonly linked with fertility, passion, vitality, and protection from bad luck. Some versions say the garment should be discarded after New Year's Day, although details vary.
The color red has long carried strong symbolic associations in many cultures, including power and celebration. Italian regional customs are not uniform, so the underwear tradition is better treated as popular folklore than as a formal religious observance.
The custom is sometimes confused with Italy's broader New Year's food traditions. Lentils are commonly served because their coin-like shape suggests wealth, while cotechino or zampone may accompany them. Those foods are separate symbols from the red garment.