Tomnice was formerly part of the German Empire. In the German Empire, the place was called Tomnitz (Kr. Krotoschin).
The place is now called Tomnice and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Tomnice | German Empire | Krotoschin | before the Versailles Treaty |
| Tomnitz | German Empire | Krotoschin | before the Versailles Treaty |
| Tomnice | Poland | Krotoszyn | after the Versailles Treaty |
| Tomnitz | German Empire | Krotoschin | 1939 |
| Tomnitz (Kr. Krotoschin) | German Empire | Krotoschin | 1939 |
| Tomnice | Poland | Krotoszyn | 1945 |
| Tomnice | Poland | Kalisz | 1992 |