Home Postcode finder NT Mount Johns Mount Johns postcode NT Mount Johns is a locality in Northern Territory covered by postcode 0870. Postcode 0870 State or territory Northern Territory (NT) Region Adelaide Add a free Mount Johns business listing Be the first listing in Mount Johns Common questionsWhat is the postcode for Mount Johns?Mount Johns, NT has the postcode 0870.What state is Mount Johns in?Mount Johns is in Northern Territory (NT).Does postcode 0870 cover more than one suburb?Yes. Postcode 0870 covers 20 localities, so the postcode alone does not identify Mount Johns. Browse other postcodes in Northern Territory , or widen the search to every Australian postcode.