Electroless nickel-phosphorus plating is a chemical process that deposits an even layer of nickel-phosphorus alloy on the surface of a solid substrate, like metal or plastic. The process involves dipping the substrate in a water solution containing nickel salt and a phosphorus-containing reducing agent, usually a hypophosphite salt.^[1] It is the most common version of electroless nickel plating (EN plating) and is often referred to by that name. A similar process uses a borohydride reducing agent, yielding a nickel-boron coating instead.