Cognomen Sidlyar (Сидляр 
, Sidlyar 
) , throughout the world, is a rare surname. The family name Sidlyar is characteristic of Belarus, where it is a rare surname, Ukraine, and Greece, where it is a very rare surname. In absolute terms, this name is the most popular in Eastern Europe, particularly Russia, Ukraine, and Belarus. Very seldom, Sidlyar is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Сидляр | Ukraine, Belarus, Russia |
| Sidlyar | Ukraine, United Kingdom, Greece, Russia, United States |