A monochrome laser printer is one that will print only in black and white, there are no colour cartridges like cyan, magenta and yellow that are available in colour laser printers.

Usually, monochrome printers are the choice for a cheaper yet still very efficient printer, mostly used to print invoices and other black/white documentation. It reduces the need to replace as often cartridges and other essentials like drum units which can become costly on colour laser printers.