Home Postcode finder SA Mount Gambier Mount Gambier postcode SA Mount Gambier is a locality in South Australia covered by postcode 5291. Postcode 5291 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Mount Gambier business listing More business listings in Mount Gambier Businesses in Mount GambierAussie Disposals Mount Gambier155 Commercial Street East, Mount Gambier SA, Australia · 08 8725 2503Bupa Mount GambierShop 1/28 Commercial St West, Mount Gambier, SA, 5290 · 1871 812 535EDI Tree and GardenMount Gambier SA 5290, Australia · 61423951692 Common questionsWhat is the postcode for Mount Gambier?Mount Gambier, SA has the postcode 5291.What state is Mount Gambier in?Mount Gambier is in South Australia (SA).Does postcode 5291 cover more than one suburb?Yes. Postcode 5291 covers 34 localities, so the postcode alone does not identify Mount Gambier. Browse other postcodes in South Australia, or widen the search to every Australian postcode.