Tonc families are Croats and they are mostly from Orahovica area. In the past century, relatively most of Croatian residents bearing this family name were born in Orahovica area and in Rijeka. In Četekovac in Orahovica area every ninth inhabitant had the family name Tonc.
Prevalence
About 70 people with faimily name Tonc live in Croatia today, in 30 households. There were 40 of them in the middle of the past century, and their number increased by 80 percent. They are located in 6 Croatian counties and 7 other places, mostly in Cetekovac in Orahovica area (30), Osijek (10), Petrijevci in Valpovo area (<10), Rijeka (<10), and in Slatina (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.