Home Postcode finder SA Navan Navan postcode SA Navan is a locality in South Australia covered by postcode 5412. Postcode 5412 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Navan business listing Be the first listing in Navan Common questionsWhat is the postcode for Navan?Navan, SA has the postcode 5412.What state is Navan in?Navan is in South Australia (SA).Does postcode 5412 cover more than one suburb?Yes. Postcode 5412 covers 4 localities, so the postcode alone does not identify Navan. Browse other postcodes in South Australia, or widen the search to every Australian postcode.