December 31 zodiac sign
December 31 closes the month at about 9° Capricorn, the final degree of the Saturn first decan; in some years the Sun has already reached the Venus-ruled second decan beyond it.
Sun signCapricorn
- Sun at 8°–11° Capricorn
- 1st decan · Saturn
December 31 in profile
The ninth degree is the last of Capricorn’s early stretch, where the sign is still emphatic but beginning to settle. The first decan’s sub-sign is Capricorn itself, so Saturn rules twice, giving discipline, a respect for craft and a long memory. In years when the Sun has crossed 10°, Taurus becomes sub-sign and Venus sub-ruler, softening the edges with taste and comfort. A December 31 Capricorn is serious about pleasure as well as work.
Play is structured but real. They enjoy board games with complex rules, choir practice, a long project in the shed. Creativity grows from repetition: the tenth version of a recipe is the one they serve. They like making things that last, and they are quietly proud of them. Shown a beautifully made object, they ask straight away how it was done. The answer often becomes their next winter project.
Generosity is steady and practical rather than showy. They remember who needs a lift, contribute to shared costs without being asked, give time to a cause for years. Gifts are useful and well chosen. They find it harder to receive than to give. A favour returned unexpectedly can leave them oddly flustered. Accepting thanks simply, without deflecting, lets others return some of that care.
Capricorn all day
In every year from 1930 to 2040 the Sun was in Capricorn for the whole of December 31, in every time zone. This is not a cusp birthday: the nearest changes of sign fall around December 22 and January 19.
Your Moon sign depends on the year
The Sun is in the same place on December 31 every year; the Moon is not. It changes sign every two and a half days, so people who share this birthday can have any of the twelve Moon signs. Here is where it was on December 31 in recent years, from 00:00 to 23:59 UTC (an arrow means it changed sign during the day).
- 2017Gemini
- 2018Libra → Scorpio
- 2019Pisces
- 2020Cancer → Leo
- 2021Sagittarius
- 2022Aries → Taurus
- 2023Leo → Virgo
- 2024Capricorn
- 2025Taurus → Gemini
- 2026Libra
Compatible signs for a Capricorn
Sun-sign compatibility starts from the element. Capricorn gets on most easily with its own element and with the two sextile signs, and feels the strongest pull from its opposite. The full charts decide how a real pairing feels.
A gift for a December 31 birthday
A cooking class with a master baker or a set of good kitchen knives, gifts that reward practice and make the next shared meal even better.
Asked about December 31
What zodiac sign is December 31?
December 31 is Capricorn in every year: the Sun is at about 8°–11° Capricorn that day, in the sign’s 1st decan.
Is December 31 a cusp birthday?
No. The Sun is well inside Capricorn on December 31. The cusp days, when the Sun changes sign, fall around December 22 and January 19. Astrology has no blended cusp signs anyway: at any moment the Sun is in one sign.
What decan is December 31?
December 31 falls in the 1st decan of Capricorn. In the triplicity system we use, that decan belongs to Capricorn and its ruler Saturn, which colours the Capricorn Sun with a little of Capricorn. In some years the Sun crosses into the next decan during the day.
Your birthday is only the Sun
A December 31 birthday tells you where the Sun was. The Moon, the Rising sign and eight more planets each sit somewhere of their own, and they depend on the year, the hour and the place. The free calculator shows all of them.