ABSTRACT Chiral assembly of achiral conjugated polymers has emerged as a new avenue to promote (opto)electronic properties and control the angular momentum of charge carriers and photons. Solvent plays a key role in chiral emergence through the lyotropic liquid crystal (LLC) assembly pathway, yet rules underpinning solvent effect remain elusive. Here, we establish a unifying framework linking solvent quality to aggregate structure and supramolecular chirality. Using redox active conjugated polymers as model systems, we reveal two types of solution aggregation: (1) β1 aggregation, defined by fibrillar structures with weak interchain coupling and torsional backbone, promotes LLC‐mediated chiral assemblies via formation of helical fibers; (2) β2 aggregation, characterized by stacked fibrils with strong interchain coupling and reduced backbone torsion, suppresses chirality. Temperature‐dependent studies show that β2 aggregates revert to β1 upon heating, thus restoring chiral assemblies. Extending to 6 conjugated polymers across 37 polymer–solvent–temperature combinations, we demonstrate the universal link between aggregate type and chiral emergence. Further, chemical doping of chiral films derived from β1 aggregates elevates electrical conductivity by up to 100‐fold across nine polymer–solvent pairs spanning a wide range of processing conditions. These findings reveal general principles for solvent‐guided chiral assembly enabling high‐performance chiral electronics, optoelectronics and spintronics.