Near the end of the circle
The zodiac is measured from zero degrees of Aries at the March equinox round to three hundred and sixty. Pisces holds the last thirty of those, so a Sun at twenty seven degrees of Pisces sits at about three hundred and fifty seven degrees of the whole circle.
Taking noon positions from 1930 to 2035, this date lands between about 26.0 and 27.4 degrees of Pisces. Roughly three days of solar travel remain before the count restarts.
The narrowness of that band comes from the leap cycle. The date slips about six hours later against the orbit each year and every fourth February pulls it back, so a century of birthdays fits inside a degree and a half.
The closing face
Twenty seven degrees falls in the third decan of Pisces, the last of the thirty six ten degree faces. The Chaldean order runs its seven planets in a loop from the start of Aries and, because seven leaves a remainder against thirty six, finishes on Mars, the planet it began with.
The triplicity scheme gets to Mars another way, assigning the face to Scorpio. Agreement between the schemes is uncommon, so a decan ruler for this date can be quoted without the usual caveat about which system produced it.
It is worth being clear about what a face is. It marks a band of longitude and attaches a planet to it. It does not place that planet anywhere in your chart, so a Mars ruled decan says nothing about where Mars itself was at your birth.
What tradition makes of late Pisces
Older writing treats the final degrees of the zodiac as a closing rather than a beginning, and reads Mars here as gathering a diffuse sign into something with direction. Some traditions give particular attention to the last degrees of any sign, on the grounds that a planet about to change sign is read differently from one settled in the middle.
All of this is interpretation attached to a band of longitude, and it is marked as interpretation. The position is checkable; what is read into it is not, and the site keeps the two apart.
How much weight to give any of it is a judgement. Decan work is a genuine part of the tradition and older than much of what surrounds it, but practitioners treat it as a refinement of the sign rather than a replacement for one.
The rest of the chart is still open
Because the Sun is shared by everyone born within a day of you, it is the least individual placement you have. The Moon covers about thirteen degrees a day and can fall in either of two signs on 17 March, decided only by the hour.
The rising sign can be any of the twelve, since the horizon sweeps the whole zodiac in a day, and the houses shift with it. The widget above works out your solar degree from your year, hour and birthplace and reports how far you were born from the nearest sign boundary.
That is also the honest limit of a birthday page. The date fixes the Sun to within a fraction of a degree, and everything that separates you from the thousands of people who share it comes from the hour and the place instead.
Questions people ask about this
How close is 17 March to the end of Pisces?
About three degrees, which is roughly three days of solar travel. The equinox arrives around 20 March, so the date remains inside Pisces in every year.
What degree of Pisces is this birthday?
Between about twenty six and twenty seven and a half at noon, depending on where the year sits in the leap cycle. The widget above gives a single figure from your own details.
Is the last decan of Pisces the last of all of them?
Yes. Pisces is the final sign and its third face is the thirty sixth, ending at the equinox where zero degrees of Aries starts the count again.
Does being near the end of a sign weaken it?
Not in the sense of the sign counting less. Some traditions read the final degrees of any sign as a distinct condition, but a Sun at twenty seven degrees of Pisces is wholly in Pisces.
Who rules this decan?
Mars, from both the Chaldean order and the triplicity scheme. The Chaldean sequence closes on it and triplicity reaches it through Scorpio.
What should someone born on this date look up next?
The Moon sign, which needs an approximate hour, and then the Ascendant and houses, which need the hour and the birthplace. Those vary between two people born on the same day in a way the Sun does not.