Surname Йонка (Йонка 
, Jonca 
, Jonka 
) , in all the world, is quite a rare last name. The cognomen Йонка is characteristic of Bulgaria, where it is quite a common surname, North Macedonia, where it is quite a rare surname, and Albania. Measured by absolute frequency, it is the most numerous in Bulgaria, Poland, and France. Likewise, Йонка is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Йонка | Bulgaria, Ukraine |
| Jonca | Germany, France, Romania, United States, Poland |
| Jonka | Germany, France, United States, Poland, Albania |
| Ionka | Bulgaria, Georgia, Greece, United States, Venezuela |