Birčić families are Croats and they are mostly from Bosnian Posavina. In the past century, relatively most of Croatian residents bearing this family name were born in Bosanian Posavina (Modrica area) and in Omis area.
Prevalence
About 140 people with faimily name Birčić live in Croatia today, in 60 households. There were 70 of them in the middle of the past century, and their number doubled. They are located in the most of Croatian counties, in 16 cities and 23 other places, mostly in Grabovac in Omis area (15), Osijek (15), Split (15), Zagreb (10), and in Lekenik in Petrinja area (10).
Outside Croatia
Family name Birčić is present in five countries on two continents.
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.