Plonczynek was formerly part of the German Empire. In the German Empire, the place was called Plönseck.
The place is now called Płonczynek and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Plonczynek | Russian Empire | Lipno | 1914 |
| Płonczynek | Poland | Lipno | after the Versailles Treaty |
| Plönseck | German Empire | Leipe (Westpr.) | 1939 |
| Płonczynek | Poland | Lipno | 1945 |
| Płonczynek | Poland | Włocławek | 1992 |