Home Postcode finder WA Greys Plain Greys Plain postcode WA Greys Plain is a locality in Western Australia covered by postcode 6701. Postcode 6701 State or territory Western Australia (WA) Region North West Suburbs Add a free Greys Plain business listing Be the first listing in Greys Plain Common questionsWhat is the postcode for Greys Plain?Greys Plain, WA has the postcode 6701.What state is Greys Plain in?Greys Plain is in Western Australia (WA).Does postcode 6701 cover more than one suburb?Yes. Postcode 6701 covers 28 localities, so the postcode alone does not identify Greys Plain. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.