Home Postcode finder SA Tumby Bay Tumby Bay postcode SA Tumby Bay is a locality in South Australia covered by postcode 5605. Postcode 5605 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Tumby Bay business listing More business listings in Tumby Bay Businesses in Tumby BayTumby Bay Area SchoolWest Terrace · 08 86882003 Common questionsWhat is the postcode for Tumby Bay?Tumby Bay, SA has the postcode 5605.What state is Tumby Bay in?Tumby Bay is in South Australia (SA).Does postcode 5605 cover more than one suburb?Yes. Postcode 5605 covers 2 localities, so the postcode alone does not identify Tumby Bay. Browse other postcodes in South Australia, or widen the search to every Australian postcode.