Home Postcode finder SA Waterloo Waterloo postcode SA Waterloo is a locality in South Australia covered by postcode 5413. Postcode 5413 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Waterloo business listing Be the first listing in Waterloo Common questionsWhat is the postcode for Waterloo?Waterloo, SA has the postcode 5413.What state is Waterloo in?Waterloo is in South Australia (SA).Does postcode 5413 cover more than one suburb?Yes. Postcode 5413 covers 9 localities, so the postcode alone does not identify Waterloo. Browse other postcodes in South Australia, or widen the search to every Australian postcode.