In 1884 he met Claude Monet and Georges Seurat. He was struck by the systematic working methods of Seurat and by his theory of colors and became Seurat's faithful supporter, friend and heir with his description of Neo-Impressionism and Divisionism method.Under Seurat's influence he abandoned the short brushstrokes of Impressionism to experiment with scientifically juxtaposed small dots of pure color, intended to combine and blend not on the canvas but in the viewer's eye, the defining feature of Pointillism. Many of Signac's paintings are of the French coast. He loved to paint the water. He left the capital each summer, to stay in the south of France in the village of Collioure or at St. Tropez, where he bought a house and invited his friends.
Paul Signac, Albert Dubois-Pillet, Odilon Redon and Georges Seurat were among the founders of the Société des Artistes Indépendants.