Home Postcodes by state WA Holt Rock Holt Rock postcode WA Holt Rock is a locality in Western Australia covered by postcode 6355. Postcode 6355 State or territory Western Australia (WA) Region Wa Subs 2 Gsr Council area Kulin Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Add a free Holt Rock business listing Be the first listing in Holt Rock Also in postcode 6355Dunn RockWA 6355East NewdegateWA 6355Lake BiddyWA 6355Lake CammWA 6355Little ItalyWA 6355MagentaWA 6355Mount SheridanWA 6355NewdegateWA 6355South NewdegateWA 6355VarleyWA 6355 Common questionsWhat is the postcode for Holt Rock?Holt Rock, WA has the postcode 6355.What state is Holt Rock in?Holt Rock is in Western Australia (WA).What council is Holt Rock in?Holt Rock is in the Kulin local government area.Does postcode 6355 cover more than one suburb?Yes. Postcode 6355 covers 11 localities, so the postcode alone does not identify Holt Rock. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.