Which calendar system determines the date of Lunar New Year, usually between January 21 and February 20?

The lunisolar calendar determines the date of Lunar New Year, usually placing it between January 21 and February 20.

Lunar New Year is based on a calendar that follows both the phases of the Moon and the solar year. In the Chinese calendar, for example, the new year begins with the new moon that falls between late January and late February. The calendar uses adjustments, including an occasional leap month, to keep lunar months aligned with the seasons.

The celebration is observed under different names and customs across East and Southeast Asia. Chinese New Year, Vietnamese Tết and Korean Seollal are related celebrations, but they have distinct foods, rituals and cultural meanings. The exact date changes from year to year because the lunisolar system does not match the fixed Gregorian calendar.

“Lunar New Year” is therefore more precise than simply calling the holiday a January 1 celebration. January 1 follows the Gregorian calendar, while Lunar New Year follows a traditional calendar whose months begin with new moons.