Home Postcode finder SA Wilmington Wilmington postcode SA Wilmington is a locality in South Australia covered by postcode 5485. Postcode 5485 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Wilmington business listing More business listings in Wilmington Businesses in WilmingtonWilmington Primary School14 Fifth St · 08 86675112 Common questionsWhat is the postcode for Wilmington?Wilmington, SA has the postcode 5485.What state is Wilmington in?Wilmington is in South Australia (SA).Does postcode 5485 cover more than one suburb?No. Postcode 5485 covers Wilmington only, which is unusual - most Australian postcodes cover several localities. Browse other postcodes in South Australia, or widen the search to every Australian postcode.