Home Postcode finder NSWDL Seal Rocks Seal Rocks postcode NSWDL Seal Rocks is a locality in New South Wales covered by postcode 2423. Postcode 2423 State or territory New South Wales (NSWDL) Region Hunter Add a free Seal Rocks business listing Be the first listing in Seal Rocks Common questionsWhat is the postcode for Seal Rocks?Seal Rocks, NSWDL has the postcode 2423.What state is Seal Rocks in?Seal Rocks is in New South Wales (NSWDL).Does postcode 2423 cover more than one suburb?Yes. Postcode 2423 covers 20 localities, so the postcode alone does not identify Seal Rocks. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.