In 2025, the Lunar New Year begins on January 29 and ends on February 12, when the new moon appears. A lunisolar calendar is used to determine these dates – it's based on the regular cycle of the Moon's phases but is reset every year to bring it into rough agreement with the solar year and its seasons.
The Lunar New Year goes by many names: Spring Festival in China, Seollal in South Korea, and Tết in Vietnam, for example.