The state electorate of Warren-blackwood has an approximate area of 19,000 km².

It is comprised of 79 suburbs including Alexandra Bridge, Argyle, Augusta, Balbarrup, Balingup, Beelerup, Boranup, Bow Bridge, Brazier, Bridgetown, Brookhampton, Channybearup, Charley Creek, Courtenay, Deanmill, Deepdene, Denmark, Diamond Tree, Dingup, Dixvale, Donnelly River, Donnybrook, East Augusta, East Nannup and Eastbrook plus parts of another 4 suburbs.

It is comprised of 49 localities including Barrabup, Beedelup, Benjinup, Biddelia, Boorara Brook, Boyup Brook, Broke, Callcup, Carlotta, Catterick, Chowerup, Collins, Crowea, Cundinup, Darradup, Dinninup, Glenoran, Hay, Jalbarragup, Kingston, Kulikup, Lake Jasper, Lake Muir, Mayanup and Mcalinden plus parts of another 2 localities.

It is comprised of the councils of Boyup Brook, Bridgetown-greenbushes and Donnybrook-balingup plus parts of Augusta Margaret River, Manjimup, Nannup and Shire Of Denmark.

It is surrounded by the state electorates of Albany, Collie-preston, Vasse and Wagin.

It is comprised of parts of the federal electorates of Forrest and O'connor.