In Croatia, Tuzluk families are Croats (from Hrvatska Kostajnica area ). In the past century, relatively most of Croatian residents bearing this family name were born in Hrvatska Kostajnica and Sisak.
Prevalence
Only a few people with faimily name Tuzluk live in Croatia today, in three households only. There were 10 of them in the middle of the past century, and their number decreased significantly. They are located in only two naselja i to in Kastel Stari (<5) and Mracaj in Hrvatska Kostajnica area (<5).