Synastry vs. Composite Charts: How Astrology Maps Relationship Destiny

Written by: Cleo Divine
Published on: January 7, 2026
Category: Love & Compatibility

I. Synastry: The Spark of Attraction

Synastry is the comparison of two individual natal charts. It maps how Person A's planets interact with Person B's planets. This is the astrology of "chemistry." When Person A's Venus sits on Person B's Mars, the attraction is immediate and undeniable. Synastry tells us how two people feel about each other and how they trigger one another's psychological patterns.

II. The Composite Chart: The "Third Entity"

While Synastry looks at two people, a Composite Chart creates a single chart for the relationship itself. It uses the mathematical midpoints between each person's planets. The Composite Chart describes the relationship as its own entity - how the couple functions together as a unit in the eyes of the world. A relationship can have great Synastry but a difficult Composite Chart, meaning they love each other but struggle to function as a couple.

III. Key Aspects to Look For

In both charts, the aspects of the Sun, Moon, Venus, and Saturn are paramount. Saturn aspects in Synastry are often called "karmic glue" - they provide the stability needed to stay together through difficult times. Without strong Saturn aspects, even the most passionate Synastry will eventually fade.

IV. Mapping Your Future Together

Are you curious about your partner? Explore our Astrology Compatibility Report to see your Synastry in action.