Home Postcode finder QLD Mount Irving Mount Irving postcode QLD Mount Irving is a locality in Queensland covered by postcode 4401. Postcode 4401 State or territory Queensland (QLD) Region Toowoomba Region Add a free Mount Irving business listing Be the first listing in Mount Irving Common questionsWhat is the postcode for Mount Irving?Mount Irving, QLD has the postcode 4401.What state is Mount Irving in?Mount Irving is in Queensland (QLD).Does postcode 4401 cover more than one suburb?Yes. Postcode 4401 covers 16 localities, so the postcode alone does not identify Mount Irving. Browse other postcodes in Queensland, or widen the search to every Australian postcode.