Reljac families are Croats and they are mostly from Rijeka area. In the past century, relatively most of Croatian residents bearing this family name were born in Rijeka and in Rijeka area. In Prhci in Cabar every third inhabitant had the family name Reljac.
About 190 people with faimily name Reljac live in Croatia today, in 80 households. There were 260 of them in the middle of the past century, and their number decreased by 30 percent. They are only located in in 9 Croatian cities and 27 other places, mostly in Podhum in Rijeka area (45), Rijeka (20), Jelenje in Rijeka area (15), Duga Resa (10), and in Koska in Nasice area (10).
Family name Reljac is present in 6 countries on two continents. The family name "Reljac " is used by some 50 people in the United States.