Home Postcode finder QLD Peak Crossing Peak Crossing postcode QLD Peak Crossing is a locality in Queensland covered by postcode 4306. Postcode 4306 State or territory Queensland (QLD) Region Western Suburbs Add a free Peak Crossing business listing More business listings in Peak Crossing Businesses in Peak CrossingPeak Crossing State SchoolIpswich-Boonah Rd · 07 54648111 Common questionsWhat is the postcode for Peak Crossing?Peak Crossing, QLD has the postcode 4306.What state is Peak Crossing in?Peak Crossing is in Queensland (QLD).Does postcode 4306 cover more than one suburb?Yes. Postcode 4306 covers 56 localities, so the postcode alone does not identify Peak Crossing. Browse other postcodes in Queensland, or widen the search to every Australian postcode.