Home Postcode finder NSW Killcare Killcare postcode NSW Killcare is a locality in New South Wales covered by postcode 2257. Postcode 2257 State or territory New South Wales (NSW) Region Gosford Add a free Killcare business listing Be the first listing in Killcare Common questionsWhat is the postcode for Killcare?Killcare, NSW has the postcode 2257.What state is Killcare in?Killcare is in New South Wales (NSW).Does postcode 2257 cover more than one suburb?Yes. Postcode 2257 covers 12 localities, so the postcode alone does not identify Killcare. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.