Home Postcode finder SA Longwood Longwood postcode SA Longwood is a locality in South Australia covered by postcode 5153. Postcode 5153 State or territory South Australia (SA) Region Sa Subs Near 2 Add a free Longwood business listing Be the first listing in Longwood Common questionsWhat is the postcode for Longwood?Longwood, SA has the postcode 5153.What state is Longwood in?Longwood is in South Australia (SA).Does postcode 5153 cover more than one suburb?Yes. Postcode 5153 covers 13 localities, so the postcode alone does not identify Longwood. Browse other postcodes in South Australia, or widen the search to every Australian postcode.