Home Postcode finder TAS Lake St Clair Lake St Clair postcode TAS Lake St Clair is a locality in Tasmania covered by postcode 7140. Postcode 7140 State or territory Tasmania (TAS) Region Tasmania Add a free Lake St Clair business listing Be the first listing in Lake St Clair Common questionsWhat is the postcode for Lake St Clair?Lake St Clair, TAS has the postcode 7140.What state is Lake St Clair in?Lake St Clair is in Tasmania (TAS).Does postcode 7140 cover more than one suburb?Yes. Postcode 7140 covers 48 localities, so the postcode alone does not identify Lake St Clair. Browse other postcodes in Tasmania, or widen the search to every Australian postcode.