Cognomen Stepniowski (Stepniowski 
) , worldwide, is a rare last name. The surname Stepniowski is habitual in Poland, where it is a rare surname, the United States, where it is an extremely rare surname, and Germany. Measured by absolute frequency, it most frequently occurs in Poland, the United States, and Brazil. Also, Stepniowski is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Stepniowski | Poland, Canada, Brazil, Germany, United States |