Home Postcode finder SA Peterborough Peterborough postcode SA Peterborough is a locality in South Australia covered by postcode 5422. Postcode 5422 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Peterborough business listing More business listings in Peterborough Businesses in PeterboroughPeterborough High School60-78 Queen St · 08 86512306Peterborough Primary School75 Bridges St · 08 86512102St Joseph's School2 Bourke St · 08 86512449 Common questionsWhat is the postcode for Peterborough?Peterborough, SA has the postcode 5422.What state is Peterborough in?Peterborough is in South Australia (SA).Does postcode 5422 cover more than one suburb?Yes. Postcode 5422 covers 13 localities, so the postcode alone does not identify Peterborough. Browse other postcodes in South Australia, or widen the search to every Australian postcode.