Helensville is a town in the North Island of New Zealand. It is sited 40 kilometres northwest of Auckland, close to the southern extremity of the Kaipara Harbour. State Highway 16 passes through the town, connecting it to Waimauku 16 km to the south, and Kaukapakapa about 12 km to the north-east. Parakai is 2 km to the north-west. The Kaipara River runs through the town and into the Kaipara Harbour to the north.
The population was 2,532 in the 2006 Census, an increase of 315 from 2001.