Exemplary substrate electrochemical planarization apparatuses may include a chuck body defining a substrate support surface. The apparatuses may include a retaining wall extending from the chuck body. The apparatuses may include an electrolyte delivery port disposed radially inward of the retaining wall. The apparatuses may include a spindle that is positionable over the chuck body. The apparatuses may include an end effector coupled with a lower end of the spindle. The end effector may be conductive. The apparatuses may include an electric contact extending from the chuck body or retaining wall. The apparatuses may include a current source. The current source may be configured to provide an electric current to an electrolyte within an open interior defined by the retaining wall.