TL;DR: Lập Xuân is the first of the 24 solar terms, marking the start of spring in the old Eastern calendar, and in Vietnam time falls on 3 or 4 February (in 2026: 2:55 a.m. on 4 February). According to press reports, many Vietnamese families hold a simple offering with fruit, bánh chưng or bánh tét and decorate the home with green plants to welcome good fortune. In Bát Tự and the Hà Lạc method, Lập Xuân is the boundary of the stem-branch year, while Tử Vi takes the year from the first day of Tết, so a person born between the two dates can have different stem-branch years in the two systems.
What is Lập Xuân?
Lập Xuân (Start of Spring) is the first of the 24 solar terms of the old Eastern calendar and marks the beginning of spring. It is not tied to a fixed lunar date; it is set by the position of the Sun along the ecliptic. The newspaper VietNamNet cites the popular view that this is when heaven and earth bring yin and yang into harmony, and that in terms of climate it is regarded as a kind of "giao thừa" (the lunar new year's eve)[1].
In Vietnam time, from 1973 to 2100 Lập Xuân falls only on 3 or 4 February. A start on 5 February belongs to earlier years, the last being 1972. The term lasts about 15 days, until the start of Vũ Thủy (Rain Water).
On what date does Lập Xuân begin in 2026?
In 2026, Lập Xuân begins at 2:55 a.m. on 4 February, Vietnam time, which is the 17th day of the twelfth lunar month of the Ất Tỵ year, thirteen days before the Bính Ngọ Tết (17 February). It runs until Vũ Thủy begins at 22:45 on 18 February. The table below gives the start of Lập Xuân for 2025 to 2030 in Vietnam time.
| Year | Gregorian date | Start time | Lunar date |
|---|---|---|---|
| 2025 | 3 Feb 2025 | 21:07 | 6th day, first month, Ất Tỵ |
| 2026 | 4 Feb 2026 | 02:55 | 17th day, twelfth month, Ất Tỵ |
| 2027 | 4 Feb 2027 | 08:42 | 28th day, twelfth month, Bính Ngọ |
| 2028 | 4 Feb 2028 | 14:30 | 10th day, first month, Mậu Thân |
| 2029 | 3 Feb 2029 | 20:19 | 20th day, twelfth month, Mậu Thân |
| 2030 | 4 Feb 2030 | 02:08 | 3rd day, first month, Canh Tuất |
Why is Lập Xuân important in the old calendar?
The Tuế thời quảng ký (歲時廣記) by Trần Nguyên Tịnh of the Song dynasty, in its entry on the first month of spring, quotes Liu Xin's Santong calendar: "立春為正月節", that is, Lập Xuân is the sectional term that opens the first month. Because the first month counted by solar terms begins at Lập Xuân, many numerological methods take this term, not the first day of Tết, as the boundary of the year.
Hoàng Tuấn's book Kinh dịch và hệ nhị phân (The I Ching and the Binary System) states that, unlike other methods that take the year from the first day of the first lunar month, the Hà Lạc method counts the year from Lập Xuân[3]. In many years this term falls in the twelfth month of the old year, so even in the twelfth month the new year starts from Lập Xuân onward; in years when Lập Xuân falls in the first or second ten days of the first month, the days before Lập Xuân still count as the old year.
The book calls a birth in the twelfth month of the old year but after Lập Xuân a "forward shift of the birth year", and a birth in the first month of the new year but before Lập Xuân a "backward shift of the birth year"[3].
What are the customs for welcoming Lập Xuân in Vietnam?
VietNamNet describes how, on the day of Lập Xuân, many Vietnamese families hold a simple offering with fruit, bánh chưng or bánh tét and decorate the home with green plants to welcome good fortune, do good deeds and pray for blessings[1]. These customs vary by family and region; there is no common rite.
In folk belief, Lập Xuân is seen as the occasion to begin the year's undertakings such as offerings and prayers for blessings, and good deeds done on this day are believed to bring luck for the whole year. Some newspaper articles also quote feng shui practitioners on the hour and direction for setting out on Lập Xuân[2]; these are individual readings, not a shared custom.
How do old Chinese books record the welcoming of Lập Xuân?
The Hiệp kỷ biện phương thư, compiled under the Qing, in volume 12, entry Welcoming Spring (迎春), describes the officials' rite: a spring ox (春牛) and an image of the god Goumang (勾芒神) are set up in the eastern outskirts; on the day before Lập Xuân, officials of the prefectures and counties go out with ceremonial staffs, drums and music to welcome spring, sacrifice to Goumang, and bring the spring ox and the god's image back to stand inside the gates of their offices; on the day of Lập Xuân itself they "用綵仗鞭春牛", whip the spring ox with decorated staffs. The book explains this as the old idea of "出土牛送寒氣", bringing out the earthen ox to send off the cold[4].
The Tuế thời quảng ký, volume 4, entry 得玉馬, records a Lập Xuân poem with the line "土牛更為𤼵春風", the earthen ox stirs the spring wind, which shows the earthen ox was already linked to Lập Xuân in poetry before the Hiệp kỷ biện phương thư.
What is Lập Xuân in the traditional calendar?
The Hiệp kỷ biện phương thư, volume 12, entry Pentads (氣候), divides each solar term into three pentads and lists those of Lập Xuân: "立春 東風解凍 蟄蟲始振 魚陟負冰", that is, the east wind thaws the ice, hibernating insects begin to stir, and fish rise to carry the ice on their backs[4].
The Tuế thời quảng ký quotes the Zhou Shu Shixun with the same three pentads, five days each: "立春之日東風解凍後五日蟄蟲始振後五日魚上氷", that is, on the day of Lập Xuân the east wind thaws the ice, five days later hibernating insects begin to stir, and five days after that fish come up onto the ice. The third pentad here is written "魚上氷", differing from the "魚陟負冰" of the Hiệp kỷ biện phương thư.
How was Lập Xuân calculated in the old calendar?
The Tuế thời quảng ký quotes the Xiaojing apocrypha: "大寒後十五日斗艮為立春", that is, fifteen days after Đại Hàn (Major Cold), when the handle of the Big Dipper points to the Cấn (northeast) direction, it is Lập Xuân.
The modern calendar sets Lập Xuân at the moment the Sun reaches ecliptic longitude 315 degrees, so the start can be calculated to the minute. In 2026, Đại Hàn begins at 8:40 a.m. on 20 January, and Lập Xuân follows 14 days, 18 hours and 15 minutes later.
What role does Lập Xuân play in numerological systems?
In Bát Tự (Tử Bình, Four Pillars), the year pillar changes at Lập Xuân and the month pillar changes at each sectional term, with the Dần month beginning at Lập Xuân. A person born on 1 February 2025, the 4th day of the Ất Tỵ Tết, still has the Giáp Thìn year pillar, because Lập Xuân that year began at 21:07 on 3 February.
Tử Vi Đẩu Số takes the year from the first day of the lunar Tết, so the same person born on 1 February 2025 has a chart drawn for the Ất Tỵ year.
Huyền Không flying stars also counts the year from Lập Xuân: Period 9 began at Lập Xuân 2024, at 15:20 on 4 February 2024, Vietnam time.
What is special about Lập Xuân in Vietnamese culture?
Lập Xuân always falls close to Tết Nguyên Đán, but not on a fixed side of it: of the six years in the table above, Lập Xuân falls in the twelfth lunar month in three years and in the first lunar month in the other three.
