Key dates for when Aries starts
Aries season begins on the first day of spring in the Northern Hemisphere (the March equinox) and runs until about April 19–20. In tropical astrology, the Sun enters Aries at 0° around March 20 each year, marking the start of the zodiac. Exact dates shift by a day or two annually because the March equinox can fall on March 19, 20, or 21, and because of leap-year adjustments in the Gregorian calendar.
Why the start date varies
The variation is driven by the way civil calendars approximate the tropical year. The vernal equinox is an astronomical event that does not always land on the same calendar date. When the equinox occurs on March 20, the Sun formally enters Aries at 0°; if it occurs on March 21, the ingress happens a day later in most time zones. This creates small year-to-year shifts that are predictable using ephemerides or astrology software.
Typical Aries date range
Across multiple years, Aries usually spans roughly March 20 to April 19. In common usage, the sign is associated with the entire month of March from the equinox onward and often includes a few days of April. For practical purposes, if you were asking what month Aries starts, the answer is March, beginning at the March equinox and commonly extending into late March and the first third of April.
How to find the exact Aries dates for any year
To determine precise Aries start dates, consult an astronomical ephemeris or Sun sign table that lists the moment the Sun reaches 0° Aries in your time zone. These tables account for time zones and leap years, so you can align the astronomical event with local calendar dates. Online sources and astrology tools will show the exact ingress for each year, removing ambiguity about when Aries begins in a given year.
Aries at a glance
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Season | Spring (Northern Hemisphere) | Tropical zodiac convention |
| Element | Fire | Traditional Western astrology |
| Quality | Cardinal | Traditional Western astrology |
| Symbol | The Ram | Classical iconography |
| Date range (typical) | Approx. March 20–April 19 | Year-to-year variation |
| Start trigger | Sun reaches 0° Aries (vernal equinox) | Solar ecliptic longitude |
Aries in different astrology traditions
Western tropical astrology uses the vernal equinox as the Aries fixed point, while sidereal systems adjust for precession, leading to slightly different dates. Vedic astrology typically places the Sun’s entry into Aries about a month later in sidereal signs. If you need Aries timing for a specific tradition, confirm which zodiac model is being used. For most Western horoscopes and general reference, March is the month Aries starts, anchored by the equinox.
Common myths and clarifications
- The Sun does not enter Aries on a fixed calendar date every year; it depends on the equinox.
- Some printed calendars generalize Aries as March 21–April 19, but the exact start can be March 20.
- Your Sun sign is determined by the ecliptic longitude at your birth, not just the month.
- Leap years and time zones can shift ingress by hours, so always check an ephemeris for precision.
How birth timing affects sign assignment
If you were born near the cusp—within a day or two of the Sun’s ingress—your rising sign, houses, and aspects can affect whether you identify with Aries traits. The Sun sign is calculated using year, month, and day, but the exact moment of the Sun’s entry into Aries determines whether a given birth moment falls in Aries or the previous sign. For absolute certainty, use a birth-chart calculator that references an ephemeris and your precise time and location.
Summary
The month Aries starts is March, specifically on the day of the March equinox when the Sun reaches 0° Aries. Exact dates vary slightly each year, commonly from March 20 to about April 19, depending on astronomical calculations and time zones. Consult an ephemeris or reliable Sun sign table if you need precise ingress times for planning or chart work.