Osówka was formerly part of the German Empire. In the German Empire, the place was called Lossau.
The place is now called Osówka and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Osowka | Russian Empire | Rypin | 1914 |
| Osówka | Poland | Rypin | 1919 |
| Lossau | German Empire | Sichelberg | 1939 |
| Osówka | Poland | Sierpc | 1945 |
| Osówka | Poland | Płock | 1992 |