Abstract: A portable, pocket sized check writing apparatus adapted to perform standard check writing functions incorporates a rectangular box-like housing open at one end for receiving a check cartridge. A keyboard is provided on the exterior of the housing for entry of data. A microprocessor is housed within the housing for receiving, storing and retrieving data. The microprocessor is operatively connected to liquid crystal display means for visually displaying data. A print head positionable relative to the face of a check is provided for printing entries on a check which is sequentially ejected from a stack of checks contained in the check cartridge.