Siekowko was formerly part of the German Empire. In the German Empire, the place was called Klein Fließen.
The place is now called Siekówko and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Siekowko | German Empire | Schmiegel | before the Versailles Treaty |
| Siekówko | Poland | Kościan | after the Versailles Treaty |
| Klein Fließen | German Empire | Kosten (Wartheland) | 1939 |
| Siekówko | Poland | Wolsztyn | 1945 |
| Siekówko | Poland | Leszno | 1992 |