Home Postcode finder NSW Dewitt Dewitt postcode NSW Dewitt is a locality in New South Wales covered by postcode 2422. Postcode 2422 State or territory New South Wales (NSW) Region Hunter Add a free Dewitt business listing Be the first listing in Dewitt Common questionsWhat is the postcode for Dewitt?Dewitt, NSW has the postcode 2422.What state is Dewitt in?Dewitt is in New South Wales (NSW).Does postcode 2422 cover more than one suburb?Yes. Postcode 2422 covers 45 localities, so the postcode alone does not identify Dewitt. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.