Home Postcode finder SA Willamulka Willamulka postcode SA Willamulka 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 Willamulka business listing Be the first listing in Willamulka Common questionsWhat is the postcode for Willamulka?Willamulka, SA has the postcode 5554.What state is Willamulka in?Willamulka 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 Willamulka. Browse other postcodes in South Australia, or widen the search to every Australian postcode.