Home Postcode finder SA Armagh Armagh postcode SA Armagh is a locality in South Australia covered by postcode 5453. Postcode 5453 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Armagh business listing Be the first listing in Armagh Common questionsWhat is the postcode for Armagh?Armagh, SA has the postcode 5453.What state is Armagh in?Armagh is in South Australia (SA).Does postcode 5453 cover more than one suburb?Yes. Postcode 5453 covers 16 localities, so the postcode alone does not identify Armagh. Browse other postcodes in South Australia, or widen the search to every Australian postcode.