Home Postcode finder SA Belvidere Belvidere postcode SA Belvidere is a locality in South Australia covered by postcode 5255. Postcode 5255 State or territory South Australia (SA) Region Sa Subs Near 2 Add a free Belvidere business listing Be the first listing in Belvidere Common questionsWhat is the postcode for Belvidere?Belvidere, SA has the postcode 5255.What state is Belvidere in?Belvidere is in South Australia (SA).Does postcode 5255 cover more than one suburb?Yes. Postcode 5255 covers 19 localities, so the postcode alone does not identify Belvidere. Browse other postcodes in South Australia, or widen the search to every Australian postcode.