Heritage Trust Federal Credit Union has been open since 1955. It's the 9th largest credit union in South Carolina with assets totaling $641.32 Million and providing banking services to more than 50,000 members. Membership: The credit union is a member-owned financial cooperative providing financial banking services to multiple member groups, but primarily serves the military, i.e. members in the armed forces. Membership is also open to immediate family of current members.