Friendship Compatibility in Astrology

For two constructed friends, the Suns and the Moons each form a trine, the Mercuries form a square, Venus shows no link, and A's Jupiter sextiles B's Moon.

Friendship is voluntary, usually non-exclusive and rarely tied to shared money or a household. The questions change accordingly: do you enjoy each other's company, can you talk, can you be tired or upset around each other, and do you want good things for one another?

Astrologers who read friendships tend to move attention away from Mars and the Venus-Mars attraction pattern and toward the Sun, Moon, Mercury, Venus and Jupiter, with the eleventh house as a house of friends. This guide describes how that reading works. It gives no verdicts: the contacts are vocabulary for a conversation about how two people actually get along.

A contact is a relationship between a planet in one person's chart and a planet in the other's, measured in degrees. A conjunction is 0 degrees apart, a sextile 60, a square 90, a trine 120 and an opposition 180. In synastry (the comparison of two charts) an orb of about 3 to 5 degrees is common for personal planets.

Sun contacts describe whether you recognize each other's way of being. Two friends with the Sun in the same element, such as two air signs, often find each other's pace natural; a square between the Suns can still produce lively friendship, but may need patience about how each person likes to decide things.

Moon contacts add the comfort layer. A friend whose Moon trines yours may feel instantly easy to be around, while a Moon square may feel like a friend who sometimes needs different things at the same moment. Mercury contacts show how you talk: easy ones suggest shared humor and fast understanding, while tense ones suggest that you may need to explain yourselves more often.

Venus is the planet of what you enjoy and appreciate. Venus contacts between friends often show up as shared pleasures: a taste in food, music, humor or style. Jupiter, traditionally the planet of expansion and generosity, adds optimism and encouragement when it touches the other person's Sun, Moon or Venus.

A caution belongs here. Jupiter's generosity can slide into overpromising, and a very pleasant Venus contact may keep friends from raising a difficulty. Easy contacts are an invitation to enjoy the friendship, and they do not replace honesty.

In a natal chart the eleventh house covers friends, groups and hopes for the future. In a comparison, astrologers look at which of one person's planets fall in the other's eleventh house, which suggests the planet's themes appear in how you connect to each other's wider circle.

This needs a birth time and a house system. With whole-sign houses, the first house is the entire sign that is rising, so a Gemini Rising chart has Aries as its eleventh house; a friend's planet in Aries would then land there. Without a birth time, leave the houses out and read the planet contacts alone.

A chart program or the birth chart calculator on this site can supply each person's positions. Then work in this order.

1. List each person's Sun, Moon, Mercury, Venus and Jupiter by sign and degree.
2. Convert each to a position out of 360 by adding 30 for each sign passed.
3. Subtract to find the gap for each pair of planets, and use 360 minus the gap if it is over 180.
4. Compare the gap with 0, 60, 90, 120 and 180, and keep only contacts within about 4 degrees.
5. Mark each contact as flowing (sextile, trine) or tense (square, opposition), and read a conjunction by the planets involved.
6. Write one real-life example for each contact, then drop any that you cannot match to experience.

Friend A has the Sun at 12 degrees Gemini, the Moon at 3 Libra, Mercury at 25 Taurus, Venus at 20 Cancer and Jupiter at 8 Leo. Friend B has the Sun at 14 Aquarius, the Moon at 5 Gemini, Mercury at 28 Aquarius and Venus at 2 Pisces. Both are constructed. Each sign starts at a multiple of 30 (Taurus 30, Gemini 60, Cancer 90, Leo 120, Libra 180, Aquarius 300, Pisces 330).

Three of the five checks flow, one is tense and one shows nothing. A reader might say these two have easy emotional and personal rapport, with a Mercury square that suggests they sometimes talk past each other, and that Venus tells them little. That is a set of questions to ask, not a verdict. Without birth times, no houses can be used.

Do friends need the same signs? No. Many lasting friendships pair signs that tradition calls unrelated, and the quality of effort matters more. Does a tense Mercury mean we will fight? No; it suggests where explanations may help. What if the chart says easy and the friendship feels hard? Trust the friendship, and look at how you each handle plans, disagreements and reassurance in practice.

Many lasting friendships pair signs the tradition calls unrelated, so when a chart says easy and a friendship feels hard, trust the friendship.