Home Postcode finder WA Leinster Leinster postcode WA Leinster is a locality in Western Australia covered by postcode 6437. Postcode 6437 State or territory Western Australia (WA) Region Wa Subs 1 G Flds Add a free Leinster business listing More business listings in Leinster Businesses in LeinsterLeinster School1 Gledden Drive · 08 90379086 Common questionsWhat is the postcode for Leinster?Leinster, WA has the postcode 6437.What state is Leinster in?Leinster is in Western Australia (WA).Does postcode 6437 cover more than one suburb?Yes. Postcode 6437 covers 2 localities, so the postcode alone does not identify Leinster. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.