<p>Magnetorheological polishing (MRP) fluid serves as a transfer medium in magnetorheological (MR) finishing, consisting primarily of abrasives, magnetic particles, additives, and base carrier fluid. MRP fluid with high-quality polishing effect with stable performance is crucial for MR deterministic finishing. This study presents the development of a novel sustainable electrolytic magnetorheological (EMR) polishing fluid and evaluates its effectiveness in the electrochemical-based magnetorheological (ECMR) finishing process. Various electrolyte-based MR fluids were formulated and analyzed through magnetic, rheological, sedimentation, and electrical conductivity tests. For experimentation, a novel experimental setup was designed to enhance the surface finish of additively manufactured cobalt-chromium alloy workpieces. A comparative study has been performed between magnetorheological finishing process and novel electrochemical-based magnetorheological finishing process. Further, life cycle assessment has been used to access the sustainability of the developed fluid. The developed fluid has been compared with traditionally used magnetorheological polishing fluid. The analytical and experimental results indicate that the newly developed EMR fluid significantly improves surface finish compared to conventional MRP fluids. Moreover, its enhanced sustainability and reduced environmental impact make it a promising alternative for precision finishing applications.</p> Graphical Abstract <p></p>