Home Postcode finder WA Lagrange Lagrange postcode WA Lagrange is a locality in Western Australia covered by postcode 6725. Postcode 6725 State or territory Western Australia (WA) Region North West Suburbs Add a free Lagrange business listing Be the first listing in Lagrange Common questionsWhat is the postcode for Lagrange?Lagrange, WA has the postcode 6725.What state is Lagrange in?Lagrange is in Western Australia (WA).Does postcode 6725 cover more than one suburb?Yes. Postcode 6725 covers 10 localities, so the postcode alone does not identify Lagrange. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.