Born on March 21: Zodiac Sign & Birthstone

Anyone born on March 21 is a Aries. The March 21 birthstone is Aquamarine and the March 21 birth flower is the Daffodil. This is a boundary date, so in some birth years it falls under Pisces instead.

What it means to be born on March 21

A birthday on the 21st of March falls under Aries. Aries is the first sign of the zodiac, a cardinal fire sign ruled by Mars. Traditionally cast as the initiator, Aries is associated with drive, courage and a headfirst approach to new ventures. The ram is its symbol, and spring's first weeks are its season.

March 21 sits on the Pisces and Aries boundary

This date is one of the twelve changeovers in the zodiac. A tropical sign begins at the moment the sun reaches a particular point, and that moment drifts by roughly six hours a year before a leap day pulls it back. On a boundary date the crossing can therefore land on either side of the calendar day, depending on the birth year and the time zone. Charts that publish fixed dates, including ours, round it.

In practice that means a birthday on March 21 is Aries in most years and Pisces in some. Only an ephemeris for the exact birth year and time settles it. The full list of boundaries is in the cusp guide.

What weekday March 21 falls on

A common year is 365 days, which is 52 weeks plus one day, so a birthday moves forward one weekday each year and two across a leap year. Over time it visits all seven. The next time March 21 falls at a weekend is 2027, on a Sunday.

The weekday March 21 falls on over the next ten years.
Year	Weekday	Weekend?
2026	Saturday	yes
2027	Sunday	yes
2028	Tuesday	no
2029	Wednesday	no
2030	Thursday	no
2031	Friday	no
2032	Sunday	yes
2033	Monday	no
2034	Tuesday	no
2035	Wednesday	no

Your March 21 birthstone and flower

Because March 21 sits in March, your birthstone is Aquamarine, a sea blue-green gem traditionally meaning serenity, honesty and safe passage. Your birth flower is the Daffodil, which stands for new beginnings, rebirth and joy. Together they make a natural birthday pairing for a card, gift or tattoo.

Every tradition tied to March 21

Everything the calendar assigns to March 21, in one table.
Field	Value
Zodiac sign	Aries (March 21 to April 19)
Element and modality	Cardinal Fire
Ruling planet	Mars
Lucky colors	Red and Scarlet
Modern birthstone	Aquamarine, sea blue-green
Traditional birthstone	Bloodstone
Other recognized stones	Bloodstone (dark green with red flecks)
Birth flower	Daffodil, with Jonquil as secondary
Day of the year	81 of 366 and 80 of 365
On a sign boundary	yes, shared with Pisces

Aries strengths and matches

Aries is often described as courageous, energetic and confident. In the traditional element model, Aries matches most easily with Leo, Sagittarius and Gemini. Those percentages come from a published formula you can check on the method page, not from a reading.

See the full birth profile

Want the shareable card for March 21? Open the birth profile tool, pick this date, and download a card to save or share. You can also read the full March overview, or browse every date we cover.

Frequently asked questions

What zodiac sign is March 21?

Anyone born on March 21 is a Aries, a cardinal fire sign ruled by Mars. March 21 sits exactly on the boundary with Pisces, so for some birth years the answer is Pisces instead.

What is the birthstone for March 21?

The birthstone for March 21 is Aquamarine, the March birthstone, which is sea blue-green. March also recognizes Bloodstone.

What is the birth flower for March 21?

The birth flower for March 21 is the Daffodil, the March birth flower, with the Jonquil as a secondary flower.

What day of the week does March 21 fall on?

In 2026 it falls on a Saturday. Because a common year is 365 days, the weekday moves on by one each year and by two across a leap year, so it cycles through all seven over time. The table on this page lists the next ten years.

Where does March 21 fall in the year?

March 21 is day 81 of a leap year and day 80 of a common year.

Is March 21 on the cusp?

Yes. March 21 is a boundary date between Pisces and Aries. The sun does not cross the boundary at the same clock time each year, so a birthday here can belong to either sign depending on the birth year and time zone. Settling it needs an ephemeris, not a date table.

Born on March 21