The present invention relates to a printhead for an inkjet printer. The printhead includes a chassis assembly defining a plurality of spaced apart first groups of apertures and a channel. An ink distribution unit defines a plurality of ink distribution passages and a plurality of spaced apart second groups of apertures. The apertures of each second group are in fluid communication with respective ink distribution passages. The ink distribution unit is received in the channel so that the first and second groups coincide. A plurality of printhead modules is serially engaged along the chassis assembly and in fluid communication with respective first groups. The printhead modules are configured to eject ink provided from the ink distribution passages via the first and second groups.