Credit Union SA is the result of the coming together of two proud and storied South Australian credit unions. It formed from the merger of PowerState Credit Union and Satsifac Direct Credit Union in October 2009. PowerState Credit Union was registered as ETSA Employees Credit Union Co-operative in 1970. It was organised by and for public power workers and their families. Satsifac Direct Credit Union was registered way back in 1959 by and for South Australian teachers. Like all credit unions, public service is deeply ingrained in its DNA.

Australian Mutuals Archives has large record holdings of the entities that created Credit Union SA as well as modern Credit Union SA history. These include annual reports from 1972 onwards, oral history recordings, photographs, newsletters, merger documents and contemporary governance documents and reports.