Trzcianka is a town in the Greater Poland region in northwestern Poland. Since 1999, it has been part of the Greater Poland Voivodeship and Czarnków-Trzcianka County. From 1975 to 1998, it was located in the Piła Voivodeship. In May 2007, Trzcianka had 17,131 inhabitants. Trzcianka is located on the Trzcianka River, and three lakes, Sarcze, Okunie and Długie, are located within the town limits.