A printhead assembly includes an elongate extrusion defining a plurality of longitudinally extending ink channels. The extrusion also defines a plurality of first groups of holes with the holes in each group extending from respective ink channels. An elongate support defines a longitudinally extending extrusion channel in which the extrusion is received. The elongate support also defines a plurality of second groups of holes aligned with the first groups. Printhead modules are engaged along the support in fluid communication with respective second groups and are configured to eject ink supplied from the channels via respective first and second groups.