Membership in the credit union is voluntary and is open to all citizens bound by with joint work or residence, who wished to create a credit union to use its services and are willing to take on relevant commitments and responsibilities. Historically, credit unions were preceded by widespread development of credit cooperation in many countries of Europe and America. To get a loan in the credit union a shareholder must be not only a formally adopted there, but necessary pay in cash contributions, the amount and order of payment of which approved by the General Assembly and fixed by the charter. Credit unions perform the function of social protection in a vital for people sphere of financial services. They care about improving the financial literacy of the population, are working on the formation of their members and their employees. Among the U.S. credit unions, there are three groups that differ in terms of assets, shareholders, and business services. Credit cooperatives and credit unions exist in many different forms. The main differences relate to the nature of the membership and the opening of a credit institution. Credit unions historically formed as a special form of social support, initially taken upon themselves the social mission of protecting the interests of citizens in the field of financial services.