In Croatia, Koch families are generally Croats (from Vrbovsko ), very rarely Germans (from Beli Manastir area ), and . In the past century, relatively most of Croatian residents bearing this family name were born in Vukovar and Zagreb.
Prevalence
About 40 people with faimily name Koch live in Croatia today, in 30 households. There were 60 of them in the middle of the past century, and their number decreased by 40 percent. They are located in the most of Croatian counties, in 14 cities and 9 other places, mostly in Vukovar (<10), Zagreb (<10), Lonjica (<10), Vrbovsko (<5), and in Sesvete (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over thirty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.