Koporčić families are Croats and they are mostly from Pleternica area. In the past century, relatively most of Croatian residents bearing this family name were born in Slavonski Brod and in Pleternica area. In Stari Slatinik in Pleternica area every thirtieth inhabitant had the family name Koporčić.
Prevalence
About 60 people with faimily name Koporčić live in Croatia today, in 30 households. There were 110 of them in the middle of the past century, and their number halved. They are located in 7 Croatian counties, in 7 cities and four other places, mostly in Stari Slatinik in Pleternica area (20), Slavonski Brod (20), Sipanska Luka (<10), Brodski Stupnik in Pleternica area (<10), and in Zagreb (<10).
Outside Croatia
Family name Koporčić is present in four countries on three continents.
In the sources analysed in the project Acta Croatica so far, the name is mentioned over ten times, the first time 1906 in source Yearbook and Directory of Literary Society of St. Jerome 1906.