Surname Кошлер (Kosler 
, Кошлер 
, Košler ) , all around the world, is a rare cognomen. The cognomen Кошлер is characteristic of Slovenia, where it is quite a rare surname, Estonia, and Czechia, where it is a rare surname. Not in comparison with a country's population, it is commonest in Germany, Slovenia, and the United States. Much less frequently, Кошлер is the forename as well as the last name.