Jončić families are Croats and they are mostly from the Island of Vis. In the past century, relatively most of Croatian residents bearing this family name were born in Split and on the Island of Vis.
Prevalence
About 90 people with faimily name Jončić live in Croatia today, in 50 households. They are located in 6 Croatian counties, in 10 cities and four other places, mostly in Komiza on the Island of Vis (35), Split (25), Zagreb (20), Vis on the Island of Vis (<10), and in Pula (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over five times, the first time 2007 in source Encyclopaedia of Croatian Surnames.