Kosinek [kɔˈɕinɛk] (German:Augustenruh) is a settlement in the administrative district of Gmina Bierzwnik, within Choszczno County, West Pomeranian Voivodeship, in north-western Poland. It lies approximately 7km (4mi) north-west of Bierzwnik, 17km (11mi) south-east of Choszczno, and 77km (48mi) south-east of the regional capital Szczecin.

For the history of the region, see History of Pomerania.