Home Postcode finder NSW Mount Wilson Mount Wilson postcode NSW Mount Wilson is a locality in New South Wales covered by postcode 2786. Postcode 2786 State or territory New South Wales (NSW) Region Nepean Add a free Mount Wilson business listing Be the first listing in Mount Wilson Common questionsWhat is the postcode for Mount Wilson?Mount Wilson, NSW has the postcode 2786.What state is Mount Wilson in?Mount Wilson is in New South Wales (NSW).Does postcode 2786 cover more than one suburb?Yes. Postcode 2786 covers 5 localities, so the postcode alone does not identify Mount Wilson. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.