Home Postcode finder ACT Williamsdale Williamsdale postcode ACT Williamsdale is a locality in Australian Capital Territory covered by postcode 2620. Postcode 2620 State or territory Australian Capital Territory (ACT) Region Canberra Add a free Williamsdale business listing Be the first listing in Williamsdale Common questionsWhat is the postcode for Williamsdale?Williamsdale, ACT has the postcode 2620.What state is Williamsdale in?Williamsdale is in Australian Capital Territory (ACT).Does postcode 2620 cover more than one suburb?Yes. Postcode 2620 covers 29 localities, so the postcode alone does not identify Williamsdale. It also appears in 2 states or territories, so it does not identify a state either. Browse other postcodes in Australian Capital Territory, or widen the search to every Australian postcode.