A inkjet printer comprising: a body configured to receive a printhead assembly, the printhead assembly comprising at least one printhead integrated circuit having a plurality of ink ejection nozzles and an ink distribution support mounting the, or each, printhead integrated circuit, the ink distribution support being arranged, in use, to distribute ink to the nozzles; and at least one mounting feature on the body for mounting the printhead assembly at the ink distribution support, the, or each, mounting feature being configured to cooperate with a corresponding complementary reference feature of the ink distribution support upon mounting of the printhead assembly to the printer, the cooperation providing information on the location of the nozzles.