Home Postcode finder SA Matta Flat Matta Flat postcode SA Matta Flat is a locality in South Australia covered by postcode 5554. Postcode 5554 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Matta Flat business listing Be the first listing in Matta Flat Common questionsWhat is the postcode for Matta Flat?Matta Flat, SA has the postcode 5554.What state is Matta Flat in?Matta Flat is in South Australia (SA).Does postcode 5554 cover more than one suburb?Yes. Postcode 5554 covers 10 localities, so the postcode alone does not identify Matta Flat. Browse other postcodes in South Australia, or widen the search to every Australian postcode.