A tab guide is provided for aligning tab stock in a paper tray of a printer having a trail edge guide including a substantially planar sheet-engaging face and a stack height finger extending from the sheet engaging face in a process direction for engaging a top surface of a top sheet on a stack adjacent the trailing edge of the sheet. The tab guide comprises a top flange, a trailing edge flange and a mount. The top flange has a top surface and a sheet-engaging surface. The trailing edge flange has a substantially planar trailing edge-engaging surface. The mount couples the top flange and the trailing edge flange. The mount is configured to removably mount the top flange and trailing edge flange to the trail edge guide and when so mounted to position the top surface of the top flange in engagement with a bottom of the stack height finger, to position the sheet-engaging surface of the top flange in engagement with a top surface located adjacent a trailing edge of a top sheet in a stack of tab stock received in the paper tray and to position the trailing edge-engaging surface of the trailing edge flange in engagement with tabs located on the trailing edge of a plurality of the uppermost sheets in the stack of tab stock received in the paper tray.