Próchnowo was formerly part of the German Empire. In the German Empire, the place was called Prochnow, Alt.
The place is now called Próchnowo and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Alt-Prochnow | German Empire | Deutsch Krone | before the Versailles Treaty |
| Alt Prochnow | German Empire | Deutsch Krone | after the Versailles Treaty |
| Prochnow, Alt | German Empire | Deutsch Krone | 1939 |
| Próchnowo | Under Polish administration | Wałcz | 1945 |
| Próchnowo | Poland | Piła | 1992 |