Zodiac dates

The full calendar, and why the boundaries move by a day.

Zodiac sign date ranges
SignDatesElementRuler
♈ Aries March 21 – April 19 Fire Mars
♉ Taurus April 20 – May 20 Earth Venus
♊ Gemini May 21 – June 20 Air Mercury
♋ Cancer June 21 – July 22 Water Moon
♌ Leo July 23 – August 22 Fire Sun
♍ Virgo August 23 – September 22 Earth Mercury
♎ Libra September 23 – October 22 Air Venus
♏ Scorpio October 23 – November 21 Water Pluto (traditionally Mars)
♐ Sagittarius November 22 – December 21 Fire Jupiter
♑ Capricorn December 22 – January 19 Earth Saturn
♒ Aquarius January 20 – February 18 Air Uranus (traditionally Saturn)
♓ Pisces February 19 – March 20 Water Neptune (traditionally Jupiter)

Why the dates move

The zodiac starts at the spring equinox, which is an astronomical event rather than a calendar date. It falls on 19, 20 or 21 March depending on the year, because the Earth's orbit does not divide evenly into 365 days. Every sign boundary inherits that wobble.

Published tables — including the one above — use the common approximation. For most people it is correct. For anyone born within about a day of a boundary, it is a coin toss until a chart is calculated properly.

There is no such thing as a cusp

The Sun is in one sign or the other at any given instant; it does not straddle two. "Cusp" describes the uncertainty of the reader, not a state of the sky. If you were born near a boundary, the answer exists — it just needs your birth time and place to find it.

And the thirteenth sign

Ophiuchus appears in the news every few years as a discovery. It is not one. Western astrology uses the tropical zodiac, which divides the year from the equinox into twelve equal segments, and has done for two thousand years. It was never a claim about which constellation the Sun is in front of — so a thirteenth constellation changes nothing about it.