Home Postcode finder SA South Hummocks South Hummocks postcode SA South Hummocks is a locality in South Australia covered by postcode 5550. Postcode 5550 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free South Hummocks business listing Be the first listing in South Hummocks Common questionsWhat is the postcode for South Hummocks?South Hummocks, SA has the postcode 5550.What state is South Hummocks in?South Hummocks is in South Australia (SA).Does postcode 5550 cover more than one suburb?Yes. Postcode 5550 covers 8 localities, so the postcode alone does not identify South Hummocks. Browse other postcodes in South Australia, or widen the search to every Australian postcode.