cornwallis postcode nswst Home ›› Postcode Finder ›› NSWST ›› Cornwallis Cornwallis local listingsThe suburb of Cornwallis is located in NSW and has a postcode of 2756. Free cornwallis business listing! Get the first free listing in cornwallis! Search and find other Postcodes in New South Wales or widen the search to Postcodes in Australia.