Toso is spiced medicinal sake traditionally drunk during New Year celebrations in Japan.

Three sizes of cup, called sakazuki, are used starting with the smallest, and passed round with each family member or guest taking a sip along with Ocechi cuisine. It is said that the custom is now limited to an area and plain sake is often used for Toso.

At Japanese traditional Sinto-style wedding, three sizes of Sakazuki are used to exchange sake between the bride and the groom. It is also known as San-san-ku-do.