Does the BaZi Year Change at Lichun (立春) or at Lunar New Year?
Two calendars, two new-year dates, one year pillar. This page pins the exact 2026 boundary to the minute, shows the same date charted under both conventions, and explains why the gap between 立春 and Lunar New Year can move your year pillar by a full pair.
Direct answer
In classical BaZi the year pillar changes at 立春 (the Start of Spring solar term), not at Lunar New Year. In 2026 立春 falls on 4 February at 04:02:08 (Asia/Shanghai); Lunar New Year falls on 17 February. A birth between those two instants therefore has year pillar 丙午 under the classical (立春) convention and 乙巳 under the lunar-new-year convention, even though the calendar date is unambiguous.
Key terms in this page
- 立春 (Start of Spring)(lì chūn)
- — the first solar term of the year, defined by the sun reaching 315° ecliptic longitude; the BaZi year begins at this instant.
- Lunar New Year (春節)(chūn jié)
- — the first day of the first lunar month; the civil new year in Chinese culture, but not the BaZi year boundary.
- Year pillar (年柱)(nián zhù)
- — the stem-branch pair for the year of birth; it carries the year stem used in 十神 mapping for the chart's outward context.
- Dispute window(—)
- — the span between 立春 and Lunar New Year (or the reverse, depending on the year), where the two conventions disagree.
01Why a solar term, and not the first day of the lunar month
The stem-branch year is tied to the sun's position in the zodiac (the tropical year), while the lunar year is tied to the moon's cycles (twelve or thirteen lunations). The two do not start on the same day. Classical BaZi texts take 立春 as the year start because the year pillar should track the seasonal energy the chart is read against, not the civil calendar.
This is also why the month pillar is tied to solar terms rather than lunar months, and why the two boundaries are handled by one convention: the whole chart is reckoned on the solar-term cycle, with the lunar calendar used only for date display and festival references.
02Worked example and near miss: 2026's dispute window
2026 offers a clean example. 立春 is 4 February 2026 at 04:02:08 (Asia/Shanghai). Lunar New Year is 17 February 2026. Under the 立春 convention, a birth on 10 February 2026 has year pillar 丙午; under the lunar-new-year convention the same birth has 乙巳. The month pillar is the same in both readings (庚寅), so only the year pillar and everything derived from its stem change.
The near misses pin the boundary from both sides. A chart for 3 February 2026 returns 乙巳 under both conventions — the year has not yet turned. A chart for 18 February 2026 returns 丙午 under both — Lunar New Year has now passed. The disagreement is exactly the 13-day window in between, and it is a clean, verifiable pattern rather than a claim: two defensible conventions produce two different pillars for the same date.
A second near miss worth checking is the 立春 instant itself, at 04:02 on 4 February. A birth at 03:5x is still in the previous year under the classical convention; a birth at 04:0x is already in the new one. Software that rounds 立春 to the calendar day will get one of those two wrong.
03School variants and software defaults
The classical and dominant convention is 立春. It is what our charting engine uses for the year and month pillars, and what this site states in its methodology page.
The lunar-new-year convention appears in civil-almanac products and in some popular apps that reuse the lunar calendar's year number directly. It is not a fringe error, but it does misplace the year pillar for every birth inside the dispute window — which is roughly one birth in twenty-five, given a window of about 10–15 days.
A third variant exists in older texts that used the winter solstice as the year start; it is rare in modern software and is documented here only so that a chart which appears off by two years is not mistaken for a calculation bug.
04Limits: what the year pillar can and cannot settle
Switching the year convention changes the year pillar, the year stem used in Ten God mapping, and the annual fortune layer built on the year pillar. It does not change the day master, so the core personality reading and the major-luck cycles derived from the day master are unaffected.
This page does not claim that one convention is more accurate in any empirical sense. It reports what each convention outputs for concrete dates; which convention to use is a school choice, and both schools continue to produce readings for real people.
Finally, the boundary is only as precise as the birth record. A birth time recorded to the hour cannot resolve a boundary that falls inside that hour; the precise instant matters only when the time is known to the minute.
05Checklist
- The birth date was checked against the year's 立春 instant (to the minute, not the date)
- The birth date was checked against Lunar New Year for the same year
- The year pillar was compared between the two conventions for dates inside the dispute window
- The month pillar was confirmed unchanged by the convention choice
- The software's stated year convention was recorded alongside the chart
Frequently Asked Questions
I was born between 立春 and Lunar New Year. Which year pillar is right?
Both are defensible under their respective conventions. Classical BaZi uses 立春; civil-almanac products use Lunar New Year. Pick the one your practitioner uses and stay consistent with it.
Does the month pillar change with the year convention?
No. The month pillar follows the sectional terms independently, so it is the same under both conventions for the same date.
Why is 立春 on a different date each year?
立春 is the instant the sun reaches 315° ecliptic longitude. Because the tropical year is not a whole number of days, the instant moves within a small range (3–5 February) from year to year.
Is a 立春 boundary the same as the eight-character year in all schools?
It is the dominant convention and the one used by this site. Some almanac products and older texts differ, which is why this page shows both outputs for the same dates.
Does this change my major-luck cycles?
No. The major-luck cycles are derived from the month pillar and the year stem's polarity. A convention change to the year stem can affect the direction rule's input, but the cycles' start age and sequence are otherwise unchanged.
Does this affect Zi Wei Dou Shu charts too?
Zi Wei uses a different year boundary (lunar new year by the classical convention). The two systems are separate; do not carry a BaZi convention choice across to a Zi Wei chart.
How precise is the boundary in practice?
To the minute and second in the computed chart, because 立春 is an astronomical instant. A birth record accurate only to the hour cannot resolve a boundary inside that hour.
Sources reviewed on 2026-10-31
- lunar-javascript 1.7.7 (EightChar year pillar; yearInGanZhiByLiChun vs yearInGanZhi) — computed the 2026 examples on 2026-10-31; snapshot archived with the page
- 2026 solar-term table (立春 4 Feb 04:02:08, Lunar New Year 17 Feb) — engine output, archived in the same snapshot file
- 《三命通会》 year-pillar and 立春 discussion — classical basis for the 立春 year boundary
Computed values on this page were produced by running the engine versions listed above at the reviewed date; school disagreements are reported as disagreements, not resolved to a single answer.
Related entries
- Solar Terms and Calendar Conversion: Why the Month Pillar Does Not Follow the Lunar MonthHow solar terms decide the year and month pillars, how the solar-term instant and leap months are handled, and how true solar time relates to standard time.
- Reading the Year, Month, Day and Hour PillarsWhat information each of the four pillars carries, and why no pillar can be read on its own, apart from the whole chart.
- Late Zi Hour (23:00–23:59): Does the Day Pillar Change at 23:00 or at Midnight?The late Zi hour is the one boundary where two BaZi traditions disagree about the day pillar itself. This page states both conventions, shows what each one outputs for the same birth time, and explains how to tell which convention your charting software uses.
Updated 2026-10-31