Magnetic CoNiP thin film alloys were electrodeposited from chloride baths. The effects of solution composition, solution pH and film thickness on the magnetic properties, microstructure and phases of electrodeposited CoNiP films were investigated. Solution pH and NaH2PO2 concentration significantly influenced the magnetic properties of CoNiP deposits. These films when deposited from solutions of pH < 2.25 exhibited soft magnetic properties, whereas from solutions of pH > 2.25, hard magnetic deposits (H-C,H-perpendicular to approximate to 2000 Oe and H-C,H-// approximate to 1000 Oe) were obtained. X-ray diffraction revealed hcp structure consisting of nanocrystalline grains (similar to 50 nm) with preferred (002) planes as deposit P content and solution pH increased.