Immigrants from countries with more effective institutions are more likely than other immigrants to have a relationship with a bank and to use formal financial markets more extensively. The evidence that a country's institutional environment shapes beliefs—and by extension the use of financial services—provides support for policies that focus on institutional reforms in promoting financial access. After holding wealth, education, and other factors constant, the impact of institutional quality in the country of origin affects the financial market participation of all immigrant groups except those who have lived in the United States for more than 28 years. These findings are robust to alternative measures of institutional effectiveness, to controlling for additional country of origin characteristics, and to various methods for addressing potential biases caused by immigrant self-selection.