An August Virgo, born roughly August 23 to 31, falls in Virgo's first decan, the one astrologers describe as the most purely Virgo: Mercury-ruled, analytical, precise. A September Virgo usually falls in the second decan, which takes on a Saturn flavor (serious, disciplined), or the third, which takes on a Venus flavor (warmer, more aesthetic), depending on the date. The first day or two of September still belong to the first decan, though, and the dividing lines move slightly from year to year.

So the month is a rough shortcut, not the real measure. Here's what decans are, where Virgo's fall on the calendar, and how much weight they deserve.

What a decan is

The zodiac is a circle of 360 degrees, divided into twelve signs of 30 degrees each. Each sign can be divided again into three parts of 10 degrees. Those parts are the decans; the word comes from the Greek for ten.

The idea is old. Ancient Egyptian astronomers used 36 groups of stars, also called decans, to tell the time at night, and Hellenistic astrologers later fitted that number onto the zodiac as three 10-degree sections per sign. Today decans are a way of adding nuance within a sign, a little like knowing which end of a country someone grew up in.

Two systems are in use:

  • The triplicity system. This is the one most modern horoscope writers use, and the one this article follows. The first decan of a sign belongs to the sign itself. The second takes on the next sign of the same element, and the third takes on the one after that. Each decan borrows the ruler of the sign it takes on.
  • The Chaldean system. Also called the faces, this older scheme hands out the planets in a fixed repeating order and gives different rulers. In it, Virgo's first decan belongs to the Sun, so if you've seen a different list elsewhere, that's probably why.

Virgo is an earth sign, and the earth signs in zodiac order starting from Virgo are Virgo, Capricorn and Taurus. So in the triplicity system, Virgo's three decans are ruled by Mercury, Saturn and Venus.

Where the months fall in Virgo's decans

The Sun moves through the zodiac at roughly one degree a day, a touch less in late summer. That's why each decan lasts about ten days, and why your birth month is only a rough guide:

  • First decan, 0 to 10 degrees Virgo: about August 23 to September 1. Ruled by Mercury.
  • Second decan, 10 to 20 degrees: about September 2 to September 12. Mercury colored by Saturn, borrowed from Capricorn.
  • Third decan, 20 to 30 degrees: about September 13 to September 22. Mercury colored by Venus, borrowed from Taurus.

Notice the overlap. "August Virgo" maps neatly onto the first decan, but that decan also takes in the first day or so of September. "September Virgo" isn't one group at all: it touches all three decans and is mostly the second and third.

The exact dates move by about a day from year to year, because the Sun reaches each degree at a slightly different moment each year, and your time zone can shift the date too. If your birthday falls on September 1 to 3, around September 12 or 13, or on the sign's own edges, the only way to know is the Sun's exact degree. A free birth chart will show it, for example "Sun at 11 degrees Virgo," which places you in the second decan.

The August Virgo: Mercury twice over

The first decan is Virgo's own, so Mercury gets a double emphasis. Astrologers tend to describe first-decan Virgos as the textbook version of the sign: observant, quick, analytical, verbal, practical and keen to improve whatever they touch. The sign's restlessness and its talent for detail are often said to be most visible here, along with its habit of worrying.

If your Virgo friend proofreads the group chat and has firm views on the best route to the airport, this is the decan people have in mind. For the sign's core traits, see our Virgo traits page.

Early to mid September: the Saturn decan

The second decan takes on Capricorn and its ruler, Saturn. Astrologers often describe this Virgo as more serious, steady and ambitious: the same eye for detail, pointed at long-term goals. Saturn stands for structure and responsibility, so this decan is associated with patience, a strong work ethic and a certain reserve.

The flip side, in this tradition, is a heavier streak of caution and self-criticism. Saturn and Mercury together can describe someone who plans everything carefully and is slow to call anything finished.

Late September: the Venus decan

The third decan takes on Taurus and its ruler, Venus. Astrologers describe this Virgo as warmer, more sensual and more tuned to beauty and comfort: the Virgo who notices the lighting in a room is wrong, cooks with care and wants things to be lovely as well as correct.

In this tradition, Venus also softens Virgo's critical edge, adding patience and an interest in relationships. Third-decan Virgos are sometimes called the most relaxed of the three, though relaxed is relative for this sign.

How much weight to give your decan

Decans are a nuance, not a separate personality. Within astrology, your Moon sign, rising sign, the placements of Mercury and Venus, and the aspects between planets all count for more than which third of Virgo your Sun is in. A Virgo with a Leo Moon will seem more expressive than any decan description; one with Sagittarius rising may seem breezier than all three.

And as with all astrology, decans are a tool for reflection, not a scientific measure of personality. If a description fits, it can be a useful mirror. If it doesn't, that says more about the limits of a ten-day category than about you. For a fuller picture, our guide to Virgo man personality traits and the explainer on what your sun sign is and isn't are good next reads.

Questions readers ask

Which Virgo decan am I?

Look up your Sun's exact degree. Zero to just under 10 degrees Virgo is the first decan, 10 to just under 20 the second, and 20 to 30 the third. The calendar dates above are a close guide, but a chart settles it, especially for birthdays near September 2 or September 12.

Are August Virgos different from September Virgos?

In decan terms, August Virgos are first decan while most September Virgos are second or third, so astrologers describe them a little differently. The differences are subtle, and other chart factors matter more. Two Virgos born on the same day can still be very different people.

Is someone born on September 22 a Virgo or a Libra?

It depends on the year, the time and the place. The Sun usually enters Libra on September 22 or 23, so a birthday right on the boundary needs a chart to confirm it.

Do Virgo decans affect compatibility?

Only a little, in that each decan carries a hint of another earth sign. For relationships, astrologers compare both full charts rather than decans. If you want to start with your own chart in depth, a natal chart report covers far more than any single detail.