Electropolishing, sometimes called reverse electroplating, is an electrochemical process which polishes a metal surface by removing a microscopic amounts of material from the work piece.

In electropolishing, the metal work piece is immersed in a temperature controlled bath of electrolyte and connected to the positive terminal (anode) of a DC power supply. The negative terminal is attached to a cathode to which the particles removed from the anode (the work piece) are attracted when electric current is applied. Often, the size, position and distance of the cathode to the work piece is controlled during the process in order to achieve the desired level of polish and to localize areas of polish.

The process also passivates the surface by leaving a very thin layer of chromium-enriched material.