Big Radio 4 or Big Radio - Četvrti program (Domaćica) is a Bosnian local commercial radio station, broadcasting from Banja Luka, Bosnia and Herzegovina. This radio station broadcasts a variety of programs such as domestic Ex Yu pop music for all ages and local news. The owner of the radio station is the company BIG RADIO d.o.o. Banja Luka. Program of is mainly produced in Serbian language at one FM frequency (Banja Luka 98.6 MHz) and it is available in the city of Banja Luka as well as in nearby municipalities Laktaši, Čelinac, Prnjavor, Bosanska Gradiška/Gradiška and Kotor Varoš.