A printhead assembly is provided having a pagewidth inkjet printhead and an ink distribution system. The ink distribution system has a longitudinal distribution housing having ducts extending longitudinally therealong which each correspond to a different ink, a longitudinal cover cooperating with the housing and having ink inlet ports which each correspond to, and are in fluid communication with, one of the ducts and being, and a laminated ink distribution structure fixed to the housing for distributing ink from the ducts to the printhead. The distribution structure includes multiple layers positioned one upon another with at least one of the layers having ink holes therethrough. Each ink hole conveys ink from one of the ducts en route to the printhead. At least some of the layers has an array of aligned air holes therethrough.