Housing prices are on track to rise 4 per cent a month over the next six months in chronically undersupplied areas of Sydney, defying the surge in listings that has taken some heat out of the market in the NSW capital.

Demand most strongly outpaces supply in Pittwater, Warringah and Sutherland, while prices will also keep rising in Newcastle, Gosford, Port Stephens and the Snowy Mountains, where listings remained low relative to demand, data provider and consultancy Suburbtrends says.