Family name Костнер (Kostner 
, Costner 
, Костнер 
) , all over the world, is quite a rare last name. The cognomen Костнер is characteristic of Austria, where it is quite a rare surname, Italy, and the United States, where it is a rare surname. Very seldom, Костнер is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kostner | United States, Germany, Czechia, Italy, Austria |
| Costner | Canada, United States, Germany, Indonesia, Italy |
| Костнер | Russia, Kazakhstan |