Sewoon: How the Yearly Cycle Is Read (and Why It Never Decides Alone)

The yearly cycle is one stem-branch pair applied to every chart at once, and it ranks third behind the natal chart and the ten-year cycle.

Sewoon (세운, 歲運) is the stem-branch pair of the current year, read against a natal chart. Everyone shares the same pair: 2026 is 丙午 Byeong-O for every chart on earth, and 2027 is 丁未 Jeong-Mi. What differs is the relationship between those two characters and each person's Day Master. The year sits third in the reading order, after the natal chart and the daewoon, and it modifies what those two have already set.

When the year changes

The Saju year does not turn over on January 1, and it does not turn over at Lunar New Year either. It changes at Ipchun (입춘, 立春), the first solar term (절기, 節氣) of the cycle, when the sun reaches 315 degrees of celestial longitude.

In 2026 that moment was February 4 at 05:02 KST. A birth on February 3, 2026 belongs to the 乙巳 Eul-Sa year. A birth on February 4 at 06:00 belongs to 丙午 Byeong-O. Lunar New Year fell on February 17, 2026, thirteen days after the pillar had already changed, which is why a zodiac animal from a household calendar and the Year Branch in a Saju chart can disagree for anyone born in that window.

The 丁未 Jeong-Mi year begins at Ipchun 2027, on February 4, 2027 at 10:46 KST. Until then the sewoon for every chart is 丙午.

The same year, ten different readings

丙 Byeong is Yang Fire. What it is to a chart depends on the Day Master (일간, 日干, ilgan), because the Ten Gods are relationships, and a relationship needs a reference point.

Two steps produce the label. First, place Fire on the generating and controlling cycles relative to the Day Master's element. Second, compare polarity: 丙 is yang, so a yang Day Master gets the matching-polarity label of its family and a yin Day Master gets the other one.

Day Master	Fire's relationship to it	Family	Ten Gods label for 丙 in 2026
甲 Gap, Yang Wood	Wood produces Fire	Output	Siksin
乙 Eul, Yin Wood	Wood produces Fire	Output	Sanggwan
丙 Byeong, Yang Fire	Same element	Companion	Bigyeon
丁 Jeong, Yin Fire	Same element	Companion	Geopjae
戊 Mu, Yang Earth	Fire produces Earth	Resource	Pyeonin
己 Gi, Yin Earth	Fire produces Earth	Resource	Jeongin
庚 Gyeong, Yang Metal	Fire controls Metal	Power	Pyeongwan (Chilsal)
辛 Sin, Yin Metal	Fire controls Metal	Power	Jeonggwan
壬 Im, Yang Water	Water controls Fire	Wealth	Pyeonjae
癸 Gye, Yin Water	Water controls Fire	Wealth	Jeongjae

The 午 O branch carries Fire too, with 丁 as its main hidden stem, so the branch repeats the Fire relationship with the opposite polarity. For a Gyeong 庚 Metal chart, 2026 is a Power year twice over. One calendar, ten readings, and that is before any natal branch has been consulted.

There is a finer grain below the year. Wolun (월운, 月運) is the monthly pillar, which changes at each solar term exactly as the natal Month Pillar does, so the 乙未 Eul-Mi month of 2026 runs from Soseo on July 7 to Ipchu on August 7. Monthly readings exist and some practitioners use them. This article stays at the year, which is the layer most readers actually meet.

The reading order

Natal chart first. Daewoon second. Sewoon third.

The natal eight characters fix the Day Master, the season, the element balance and every structural relationship. The daewoon sets the ten-year conditions those characters sit inside. The sewoon adjusts the current year within that decade.

The consequence is that a year cannot override what the two layers above it have set. A 丙午 year read against a Gap 甲 Wood chart in a 丁酉 Jeong-Yu daewoon is an Output year inside an Output-and-Power decade. The same year against the same chart in a 壬辰 Im-Jin daewoon is an Output year inside a Resource decade, with Water on the cycle stem above the Fire. Identical table label. Different reading.

This is also why the sewoon gets more attention in Korea than its rank deserves. It changes every February and it applies to everyone, so it is the one layer a reader can discuss without knowing the client's full chart. New Year readings, whether at Ipchun or at the lunar holiday thirteen days later, are a habit built on the fact that this one pair has moved. The habit is reasonable. Treating the year as the whole reading is a different matter.

The year-clash question

Six of the twelve branches pair off as clashes (충, 沖): 子 with 午, 丑 with 未, 寅 with 申, 卯 with 酉, 辰 with 戌, 巳 with 亥. When the year branch is one half of a pair and a natal branch is the other, the tradition reads that year as one where the structure around that natal branch is disturbed.

A chart with a Ja 子 day branch meets 2026, a 午 O year, as a day-branch clash. In Saju, this is traditionally interpreted as a year in which the arrangements attached to the Day Pillar, which the tradition associates with the self and the domestic sphere, are moved or tested. Whether the disturbance reads as pressure or as release depends on what 子 Water was doing in the chart: a Water Day Master rooted only in that branch loses footing for the year, while a Fire Day Master that 子 was controlling gets a year with less of that control.

Traditional readers describe a clash year in terms of things being moved or brought to a decision, and that is the register we use. It is a structural relationship between two characters, dated to a year, and readable in advance. That is all it is.

Pattern questions for the current year

Take the table label for your Day Master and hold it against 2026 as it has been so far:

If 丙 is Output for you, which project or statement did you put into the open this year that you had held back in 2025?
If 丙 is Power for you, which rule or deadline pressed harder this year than the year before, and did you meet it by complying or by restructuring?
If 丙 is Wealth for you, what did you take on to manage this year, and was the capacity there for it?
If 丙 is Resource or Companion for you, who or what supplied support this year, and did you use it or store it?

Then ask whether the answer would have been the same in 2025, a 乙巳 Eul-Sa year with Wood on the stem. If it would, the year label is doing no work.

What this can and cannot tell you

The calendar facts are fixed: which pair the year is, when it changed and which label it takes against each Day Master. The interpretation is a tradition, not a validated predictive method, and we don't present it as one. Kairo doesn't make event predictions, and a year pillar is the layer with the least information in it. Two characters, shared by everyone alive, ranked third. The chart above them decides what they mean.