The decision to amalgamate the two parties means a significant consolidation of the conservative movement nationally.
It is understood to have been ratified by executives from Family First who have resolved not to keep the party going at state or federal level and to instead join with Senator Bernardi's new party.
When Family First is wound up, the party's resources will go to the Australian Conservatives.
Senator Bernardi is the federal parliamentary leader of the Australian Conservatives.
In South Australia, Dennis Hood and Robert Brokenshire, who are both members of the State Upper House, will switch from Family First to representing the Australian Conservatives.
Immigration Minister Peter Dutton said the amalgamation was a natural fit.
"My sense is that it was inevitable," he told Sky News.