December Zodiac Sign: Sagittarius or Capricorn? Dates, Traits & Solstice Cusp

December is split between two zodiac signs: Sagittarius, which runs from the start of the month through December 21, and Capricorn, which takes over from December 22 and continues into January. Sagittarius is an adventurous, freedom-loving Fire sign ruled by Jupiter; Capricorn is a disciplined, ambitious Earth sign ruled by Saturn. Anyone born between roughly December 19 and December 25 is often called a Sagittarius-Capricorn cusp, though astrologically the Sun is always in exactly one sign, never a blend of two.

As with September's Virgo-Libra cusp lining up with the autumn equinox, December's cusp has a real astronomical anchor: the Sun's move into Capricorn happens on the same day as the winter solstice, the shortest day of the year in the Northern Hemisphere. Below is the exact date breakdown, a side-by-side comparison of the two signs, and what that solstice link means for anyone born right on the boundary.

Which Zodiac Sign Is December?

Quick answer: early-to-mid December is Sagittarius, late December is Capricorn.

Sagittarius's full range extends from November 22 to December 21, so anyone born in the first three weeks of December is a Sagittarius regardless of where the month started. Capricorn's full range runs December 22 to January 19, meaning it's the one sign that spills across the New Year — the last third of December and the first three weeks of January both belong to Capricorn.

Sagittarius vs. Capricorn: December Zodiac Traits

The two halves of December produce very different personalities, since Fire and Earth signs operate on opposite instincts — one chases expansion, the other builds structure.

These are general tendencies used in popular astrology, not fixed rules — two people born a week apart in the same sign can still turn out very differently.

Born Between December 19–25? The Sagittarius-Capricorn Cusp, Explained

A birthday in the last few days of Sagittarius or the first few days of Capricorn is commonly called being born "on the cusp," sometimes referred to as the "Cusp of Prophecy." As with every zodiac cusp, a planet can only occupy one zodiac sign at a time, so a Sun sign is never technically a blend of two signs — it's always one or the other.

What sets this cusp apart, much like September's Virgo-Libra boundary, is that it's anchored to a real astronomical event: the winter solstice, the day the Northern Hemisphere receives the least daylight of the year. Capricorn season is defined to begin at that exact turning point, when the Sun reaches its lowest position in the sky before days slowly start lengthening again — which is part of why Capricorn carries themes of endurance, discipline, and building quietly through hard conditions.

That said, the solstice itself doesn't fall on the same calendar date every year — it typically lands on December 21 or 22, shifting because the calendar year and Earth's orbit don't divide evenly, the same leap-year drift responsible for cusp-date variation in every month. For a birthday that falls right on that boundary, the only way to know the exact Sun sign is to check the exact date, time, and location of birth against an ephemeris or birth chart calculator.

If a birthday falls clearly within December 19–20 or December 23–25, the sign is essentially certain (Sagittarius and Capricorn respectively) — it's really only December 21–22 itself where the year-to-year shift can matter.

December Zodiac Sign by Specific Day

• December 1–21: Sagittarius
• December 19–21: Sagittarius, but within the cusp window — check an exact birth chart if born on December 21
• December 22–25: Capricorn, but within the cusp window — check an exact birth chart if born on December 22
• December 22–31: Capricorn

Famous People Born in December

A mix of well-known Sagittariuses and Capricorns, by birth date:

• Sagittarius: Taylor Swift (December 13), Nicki Minaj (December 8), Jake Gyllenhaal (December 19)
• Capricorn: Michelle Obama (January 17, often cited alongside late-December Capricorns), Kate Middleton (January 9), LeBron James (December 30)

Note: birth dates are a matter of public record, but a Sun sign alone doesn't capture a person's full astrological profile — that requires a complete birth chart.

Frequently Asked Questions

What zodiac signs are in December?

December has two: Sagittarius, from the 1st through the 21st, and Capricorn, from the 22nd through the 31st (Capricorn then continues into January).

Is December 21 a Sagittarius or a Capricorn?

Almost always Sagittarius, since Sagittarius's range extends through December 21 in most years. Because the exact sign change happens at a specific hour tied to the solstice rather than at midnight, a small number of December 21 births in certain years can technically fall just after the shift into Capricorn — worth checking an exact birth chart if the timing matters.

Is December 22 a Sagittarius or a Capricorn?

Almost always Capricorn, for the same reason: the solstice, and with it the sign change, can land on the 21st or the 22nd depending on the year.

Why does the Sagittarius-Capricorn cusp line up with the winter solstice?

Because Capricorn season is defined to begin at the winter solstice, the point of least daylight in the Northern Hemisphere. Every other zodiac sign change is just a calendar date; this one, like Libra's start at the autumn equinox, is tied to an actual astronomical event.

What element and planet rule the December zodiac signs?

Sagittarius is a Fire sign ruled by Jupiter; Capricorn is an Earth sign ruled by Saturn.