In Croatia, Kosmačin families are generally Croats (from Varazdin ), very rarely Slovenes (from Slovenia ). In the past century, relatively most of Croatian residents bearing this family name were born in Varazdin and Zagreb.
Prevalence
About 20 people with faimily name Kosmačin live in Croatia today, in 9 households. There were 20 of them in the middle of the past century, and their number remains constant. They are located in four Croatian counties, threee cities and 5 other places, mostly in Zagreb (<10), Varazdin (<5), Vucetinec in Cakovec area (<5), Ivanec (<5), and in Nustar in Vinkovci area (<5).
Outside Croatia
Family name Kosmačin is present in three countries.