Cognomen Леффлер (Leffler 
, Леффлер 
) , throughout the world, is quite a common last name. The family name Леффлер is habitual in Sweden, where it is quite a rare surname, the United States, and Germany.
| VARIANT | COUNTRY |
|---|---|
| Leffler | Germany, Sweden, United States, Argentina, Canada |
| Леффлер | Kazakhstan, Russia, Ukraine |