Home Postcode finder WA Kookynie Kookynie postcode WA Kookynie is a locality in Western Australia covered by postcode 6431. Postcode 6431 State or territory Western Australia (WA) Region Wa Subs 1 G Flds Add a free Kookynie business listing Be the first listing in Kookynie Common questionsWhat is the postcode for Kookynie?Kookynie, WA has the postcode 6431.What state is Kookynie in?Kookynie is in Western Australia (WA).Does postcode 6431 cover more than one suburb?Yes. Postcode 6431 covers 13 localities, so the postcode alone does not identify Kookynie. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.