The design and performance of a small-scale vertical flow constructed wetland (VFCW) system, for on-site treatment of domestic wastewater, are presented. The system serves a two-story, two-family (8 persons) building, and comprises three treatment stages: two settling tanks in series, a VFCW and a zeolite tank. The treatment performance of the system was monitored on a weekly basis for about forty months. Results show a satisfactory performance with the following mean removal efficiencies: 96.4% for BOD, 94.4% for COD, 90.8% for TKN, 92.8% for ammonia, 61.6% for OP and 69.8% for TP. The zeolite was found to offer additional removal of nitrogen, total phosphorus and organic matter. The zeolite saturation time is estimated