Abstract Immigrant informal banking relies on trust, norms and networks to keep agreements rather than laws, courts, or written contracts. Although research exists on the sociological and economic dimensions of informal banking, this study examines them comparatively with explicit attention to the role of public action. Policy decisions targeted Eastern European unincorporated banks in 1917 and Haitian essos in 1998. I assessed how immigrants with equivalent levels of social capital influenced and are affected by laws creating postal savings banks, state chartered neighborhood banks and liberalized underwriting for mortgages. This research shows that government intervention lowered barriers to bank ownership and services, which increased working class access to cheap sources of credit, an important move in overcoming inequalities in homeownership, small business development and other mechanisms of mobility. These changes transformed informal practices from a liability that justified economic discrimination and exclusion to a resource for creating a more democratic and inclusive formal banking sector. Political movements embedded in public interest and social welfare networks created these policy shifts, rather than ethnic interest groups or immigrant civic participation. As a result, policy advocacy by elites actually constructed “bottom-up,” community-based financial institutions. In these new sites for formal banking, immigrant community knowledge found legitimacy, giving their social ties new viability in these venues. Examining the political development of community banking institutions illuminates how the politics of policy designs, rather than immigrant political participation, has re-configured the structure of service delivery and constitutes another dimension of the state’s role in incorporating immigrants. Read chapter one hereRead full dissertation here