Home Postcode finder NSW Gelston Park Gelston Park postcode NSW Gelston Park is a locality in New South Wales covered by postcode 2650. Postcode 2650 State or territory New South Wales (NSW) Region Canberra Add a free Gelston Park business listing Be the first listing in Gelston Park Common questionsWhat is the postcode for Gelston Park?Gelston Park, NSW has the postcode 2650.What state is Gelston Park in?Gelston Park is in New South Wales (NSW).Does postcode 2650 cover more than one suburb?Yes. Postcode 2650 covers 52 localities, so the postcode alone does not identify Gelston Park. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.