Pisces and Sagittarius compatibility has a twin. Gemini and Virgo form the same kind of pair. Both pairs join two mutable signs, the signs that close a season. Both sit three signs apart, in a square. And one planet rules each pair: Mercury for Gemini and Virgo, Jupiter for Sagittarius and Pisces.
The twins differ in one plain way. Gemini and Virgo fall in late spring and late summer. Sagittarius and Pisces fall in late fall and late winter. That shift changes how common the pair is. About one random US couple in 78 is a Pisces and a Sagittarius. For Gemini and Virgo, it is one couple in 65. So the winter twin is about 20 percent rarer.
This page shows where that gap comes from. Half of it is the shape of Earth’s orbit. The other half is the US birth calendar. Then it checks what the old books say about the pair, and what a census of real marriages found. Read all of it as a lens, not a forecast.
The short version
| Question | What we found. |
|---|---|
| How common is the pair in the US? | About 1 random couple in 78, the 58th most common of 66 mixed pairs. |
| What is its twin? | Gemini and Virgo, the same mutable square with one ruler, at about 1 couple in 65. |
| Why is this pair rarer? | Shorter Sun seasons explain half the gap, and fewer births per day explain the other half. |
| What angle links the signs? | A square, three signs or 90 degrees apart. |
| How many couples have an exact square? | About 36 percent, if you allow 6 degrees of slack. |
| How did the pair do in the 2001 census? | Second lowest of 66 mixed pairs, 0.73 percent below chance, which is noise. |
| Can a Pisces have Venus in Sagittarius? | Never, and the reverse never happens either. |
First, what no one can promise
Astrology is not a science. No study has shown that a Sun sign predicts whether a couple will last. So this page gives the pair no score. It uses the old symbols as a way to talk about two styles of life.
Your Sun sign is the slice of sky the Sun stood in when you were born. Each slice is 30 degrees wide. Sagittarius runs from about November 22 to December 21. Pisces runs from about February 19 to March 20. The exact hour shifts a little each year, as our guide to the zodiac signs shows.
How common is a Pisces and Sagittarius couple?
The signs are not the same size in the birth count. We use one reference for all our pair pages. It holds 62.2 million US births from 2000 to 2014, counted day by day. In that count, 8.04 percent of babies are Pisces. Only 7.95 percent are Sagittarius.
Now pair two people at random. The couple can be a Pisces woman with a Sagittarius man, or the reverse. Both count. So the chance is two times 8.04 percent times 7.95 percent. That gives 1.28 percent, or about 1 couple in 78.
| Pair of signs | Chance for a random US couple. |
|---|---|
| Leo and Virgo, the most common mixed pair | About 1 in 62. |
| Gemini and Virgo, the summer twin | About 1 in 65. |
| What an even split would give | 1 in 72. |
| Pisces and Sagittarius, the winter twin | About 1 in 78. |
| Capricorn and Aquarius, the rarest mixed pair | About 1 in 83. |
So Pisces and Sagittarius rank 58th of the 66 mixed pairs. Only eight mixed pairs are rarer. Both signs pull the pair down. Sagittarius is the third rarest Sun sign in US births, and Pisces is the fourth rarest.
The summer twin: Gemini and Virgo
Four signs close a season. Gemini ends spring. Virgo ends summer. Sagittarius ends fall. Pisces ends winter. Today we call them the mutable signs. The four form a cross on the wheel, each one a square from its two neighbors on the cross.
Two old rulers split that cross. Mercury rules Gemini and Virgo. Jupiter rules Sagittarius and Pisces. So the cross holds two pairs of the same build: a square, two mutable signs, one ruler. Our page on Gemini and Virgo compatibility covers the Mercury pair. This page covers the Jupiter pair.
On paper, the two pairs are equal. In the birth count, they are not. Gemini and Virgo come to 1.53 percent of random US couples. Pisces and Sagittarius come to 1.28 percent. Divide one by the other and you get 1.20. The summer twin is about 20 percent more common.
Cause one: the Sun hurries through winter
Earth’s path around the Sun is not a perfect circle. Earth comes closest to the Sun in early January, a point called perihelion. Near that point it moves fastest. Seen from Earth, the Sun then seems to race through the signs. In early July, Earth is farthest away and moves slowest. The Sun then seems to crawl.
Sagittarius season ends about two weeks before perihelion. Pisces season starts about seven weeks after it. Both sit in the fast part of the year. Gemini and Virgo sit in the slow part. Here are the average lengths from 2000 to 2014, the years of the birth file. Over the site’s reference window, 1600 to 2400, they round to the same values.
| Sign | Days the Sun spends there. |
|---|---|
| Gemini | About 31.33 days. |
| Virgo | About 30.90 days. |
| Sagittarius | About 29.56 days. |
| Pisces | About 29.96 days. |
| The two winter signs, added | About 2.7 days fewer than the two summer signs. |
Our page on the Sagittarius sign gives the full list of season lengths. Only Capricorn is shorter than Sagittarius.
Now pretend every day of the year had the same number of births. Then the pair chance would depend on days alone. Pisces and Sagittarius would come to about 1 couple in 75. Gemini and Virgo would come to about 1 couple in 69. That is a gap of about 9 percent. So the orbit alone explains about half of the 20 percent.
Cause two: fewer babies per day
The rest comes from the birth calendar. US births are not spread evenly over the year. We took the births in each sign and divided by the days in its season. Then we compared that with the average day.
| Sign season | Births per day, against the yearly average. |
|---|---|
| Virgo | About 5.6 percent more. |
| Gemini | About 0.2 percent fewer. |
| Sagittarius | About 1.7 percent fewer. |
| Pisces | About 1.9 percent fewer. |
Virgo season holds the busiest birth days of the US year. Both winter signs sit a little below average. Put the two effects side by side. Shorter seasons give a gap of about 9 percent. Fewer births per day give about 9 percent more. Together they make the 20 percent. We checked this with a second birth file, from 1994 to 2003. The split came out the same: half orbit, half birth calendar.
None of this says a thing about love. It says how common two birth dates of this kind are, side by side. But it does answer a real question. If you are a Pisces with a Sagittarius partner, your pair is less common than most. You are not rare, though. Around 1 in 78 is still a lot of couples.
What a square means, and when it is exact
Astrologers read the angle between two signs. They call it an aspect. Sagittarius is the ninth sign. Pisces is the twelfth. Three signs apart makes 90 degrees, a square.
Ptolemy wrote the Tetrabiblos, the main old textbook of astrology, in the second century. In Book 1, chapter 13, he sorts the aspects. He calls the trine and the sextile harmonious, because they join signs of the same kind. He calls the square and the opposition disharmonious, because they join signs of opposite kinds. Sagittarius is a masculine fire sign. Pisces is a feminine water sign. So by his rule, this square is a clash of kinds.
A square by sign is not always a square by degree. Each sign is 30 degrees wide. So two Suns in these signs can sit anywhere from 60 to 120 degrees apart. An astrologer counts an aspect only when the angle is close to exact. The slack allowed is called the orb.
| Orb allowed | Share of couples with a real square. |
|---|---|
| Within 3 degrees | About 19 percent. |
| Within 6 degrees | About 36 percent. |
| Within 8 degrees | About 46 percent. |
| Within 10 degrees | About 56 percent. |
These shares are the same for any two signs three apart. The shape of the wheel sets them, not the signs. So only about one Pisces and Sagittarius couple in three has a close square between the two Suns.
What the old books say about the two signs
Two double-bodied signs
In chapter 11, Ptolemy calls four signs bicorporeal, which means double-bodied: Gemini, Virgo, Sagittarius and Pisces. He says they come between the fixed signs and the turning points of the year. So each one shares the weather of two seasons. Sagittarius holds the end of fall and the start of winter. Pisces holds the end of winter and the start of spring.
The pictures match the name. Pisces is two fish. Sagittarius is half man and half horse. Modern writers turn this into a trait: both signs change shape to fit what comes next. That is a reading, not a finding. But it is the oldest tie these two signs share.
Jupiter’s two homes
In chapter 17, Ptolemy hands each planet two signs, one for day and one for night. Jupiter gets Sagittarius and Pisces. William Lilly kept the same table in Christian Astrology in 1647. Our page on the Pisces sign traces how Jupiter held Pisces alone until Neptune was found in 1846.
This is where the mirror with Gemini and Virgo gets neat. Lilly’s table puts each planet in exile, or detriment, in the signs across from its homes. Jupiter is in exile in Gemini and Virgo. Mercury is in exile in Sagittarius and Pisces. Mercury also has its fall, its weakest grade, in Pisces. So each twin pair is ruled by the planet the other pair keeps out.
The ties this pair lacks
Ptolemy lists more links between signs. Signs that command and obey take equal time to rise. Signs that behold each other have days of equal length. Signs with no aspect at all he calls disjunct. Pisces and Sagittarius are none of these. By his scheme, the square is their only link, and it is a tense one.
One more old rule points the same way. Venus is exalted in Pisces, meaning it is said to work at its best there. Venus has no major rank in Sagittarius. So the planet of affection is strong on one side of this pair only.
The marriage census test
The biggest test of love signs we know of was run by David Voas, a British sociologist, in 2007. He used the 2001 census of England and Wales. It held the birth dates of about 10.3 million married couples. A short version ran in the Skeptical Inquirer in March 2008.
His raw count showed too many couples with the same sign. He traced most of them to errors on the forms. Some forms had one birthday typed in for both spouses. He removed those errors and built a clean table, his Table 7. It holds about 9.5 million couples.
We read the two cells for this pair. Chance here means the count you would expect if people chose partners with no regard to sign.
| Couples in the 2001 census | Found, against chance. |
|---|---|
| Sagittarius wife, Pisces husband | 61,361 found, about 62,002 expected. |
| Pisces wife, Sagittarius husband | 61,660 found, about 61,918 expected. |
| Both cells added | About 899 fewer, or 0.73 percent. |
We did the same sum for all 66 mixed pairs. Pisces and Sagittarius came second lowest. Only Taurus and Sagittarius fell further short, at 0.93 percent.
So is the square showing up in real marriages? The numbers say no. Voas wrote that any cell could drift up to 450 couples from chance and still fit a random world. The Pisces wife cell is well inside that band. The Sagittarius wife cell, at 641 short, is one of a small scatter just outside it. Voas looked at that scatter and judged it to have no real weight. In a table this big, some cells always land at the edges. His words: the largest gap in all 144 cells was barely 1 percent.
What the pair means in a reading
Here is how astrologers read the two signs, with no promise attached. Sagittarius is fire. It reads as frank, restless and drawn to the far horizon. Pisces is water. It reads as soft, porous and drawn to the inner world. Stephen Arroyo, in Astrology, Psychology and the Four Elements, treats each element as a kind of energy. Fire and water are two very different kinds.
The mutable mode is what they share. Both signs bend. Both dislike being pinned down. That can make the pair easy going at first. It can also leave no one holding the plan. Four snags come up in the sign books, each with a small step.
| Snag | A small step. |
|---|---|
| Sagittarius says the blunt thing, and Pisces hears a wound. | Sagittarius asks first: do you want my view, or just my ear. |
| Pisces hints, and Sagittarius misses the hint. | Pisces names the wish in one plain line. |
| Both drift, and bills or plans slip. | Pick one fixed night a week for the dull tasks. |
| Sagittarius wants to roam, and Pisces reads it as leaving. | Agree on when each goes solo, and when each comes back. |
None of these steps needs a chart. Any two people with these styles can use them. That is the honest point. The signs give a name to a pattern. The fix lies in a plain talk.
Liz Greene makes a related point in her 1977 book Relating. What we find hard in a partner is what we have not yet grown in ourselves. For this pair, Sagittarius can learn to wait. Pisces can learn to say what it wants.
The Sun is one point of many
A Sun sign is one point out of at least ten in a birth chart. Comparing two full charts is called synastry. Robert Hand’s 1975 book Planets in Composite goes further and blends two charts into one. For love, three points matter more than the Sun.
The Moon shows what each person needs to feel safe. Our page on Sagittarius and Pisces Moon signs reads the pair at that level. Venus shows what a person finds lovely. Mars shows how each one goes after what they want.
Venus has a hard limit here. It never strays more than about 47 degrees from the Sun. Sagittarius and Pisces are at least 60 degrees apart. So a Pisces never has Venus in Sagittarius, and a Sagittarius never has Venus in Pisces. Their Venus signs can still meet in other ways, as our page on Pisces and Sagittarius Venus placements shows.
So a Sagittarius Sun can have a Cancer Moon. A Pisces Sun can have Mars in Leo. Each of those says more than the Sun pair does. If you know both birth dates and times, the full chart is where the detail lives.
How we measured
For the birth shares, we used daily US Social Security birth counts for 2000 to 2014, published by FiveThirtyEight. We matched each day to the exact minute the Sun changed sign, in Central time. A second file, from the National Center for Health Statistics for 1994 to 2003, gives Sagittarius 7.90 percent and Pisces 8.09 percent. The pair chance is then about 1 in 78 as well.
For the season lengths, we timed each entry of the Sun into a sign from 2000 to 2014. We did it two ways. The first used the astronomy-engine library. The second used the short solar formula in Jean Meeus’s book Astronomical Algorithms, with its own search for each entry. The two routes agree to within two minutes per season.
To split the gap, we first built a pair chance from days alone. It uses each season’s length divided by 365.24 days. Then we set that beside the real pair chance from births. The ratio of the two gaps gives the part owed to the birth calendar. Both birth files gave a split of about half and half.
For the census, we read Tables 7 and 8 in the paper by David Voas. We took the chance count for each cell as the row total times the column total, divided by the grand total. That is the same method Voas used for Table 8. For the old rules, we read Ptolemy’s Tetrabiblos, Book 1, chapters 11 to 17, in the Robbins translation, and Lilly’s table of dignities.
Frequently asked questions
Are Pisces and Sagittarius compatible?
Astrology reads them as a square, a tense link between fire and water. They share the mutable mode and the same ruler, Jupiter. No study has shown that this or any sign pair lasts longer, so treat it as a lens, not a forecast.
How common is a Pisces and Sagittarius couple?
In US birth data from 2000 to 2014, about 1 random couple in 78 is one Pisces and one Sagittarius. That ranks 58th of the 66 mixed sign pairs.
Why is this pair rarer than Gemini and Virgo?
Both are mutable squares with one ruler. But the Sun moves faster through Sagittarius and Pisces, and fewer US babies are born per day in those seasons. Each cause explains about half of the 20 percent gap.
Did Pisces and Sagittarius do badly in the marriage census?
They came second lowest of 66 mixed pairs, 0.73 percent below chance, in the 2001 census of England and Wales. David Voas judged gaps of this size to be noise.
Can a Pisces have Venus in Sagittarius?
No. Venus stays within about 47 degrees of the Sun, and the two signs are at least 60 degrees apart. A Pisces has Venus in Capricorn, Aquarius, Pisces, Aries or Taurus.
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