Groznica families are usually Croats and they are mostly from north Herzegovina , rarely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in North Herzegovina (Jablanica area) and in Ilok.
About 140 people with faimily name Groznica live in Croatia today, in 60 households. There were 40 of them in the middle of the past century, and their number more than tripled. They are located in 9 Croatian counties, in 14 cities and 9 other places, mostly in Sarengrad (50), Ilok (40), Zagreb (35), Sesvete (<10), and in Slatina (<10).
Family name Groznica is present in four countries on two continents.