Home Postcode finder SA Long Plains Long Plains postcode SA Long Plains is a locality in South Australia covered by postcode 5501. Postcode 5501 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Long Plains business listing Be the first listing in Long Plains Common questionsWhat is the postcode for Long Plains?Long Plains, SA has the postcode 5501.What state is Long Plains in?Long Plains is in South Australia (SA).Does postcode 5501 cover more than one suburb?Yes. Postcode 5501 covers 14 localities, so the postcode alone does not identify Long Plains. Browse other postcodes in South Australia, or widen the search to every Australian postcode.