Home Postcode finder VIC Castle Donnington Castle Donnington postcode VIC Castle Donnington is a locality in Victoria covered by postcode 3585. Postcode 3585 State or territory Victoria (VIC) Region Vic Far Country Add a free Castle Donnington business listing Be the first listing in Castle Donnington Common questionsWhat is the postcode for Castle Donnington?Castle Donnington, VIC has the postcode 3585.What state is Castle Donnington in?Castle Donnington is in Victoria (VIC).Does postcode 3585 cover more than one suburb?Yes. Postcode 3585 covers 15 localities, so the postcode alone does not identify Castle Donnington. Browse other postcodes in Victoria, or widen the search to every Australian postcode.