We propose an empirical study analyzing the link between monetary regime and informal monetary practices, both being within the framework of a country's monetary system, the Currency Board in Djibouti. The analytical and empirical results both from monetary accounting and from econometric simulations, particularly from different tests for cointégration between the balance of payments, reserve money and monetary informal transfers (hawalas) for the period 2002 - 2011, show that informal practices develop in line with the highly rigid monetary regime. The interaction of formal and informal sector provides a macro-monetary balance and stability, thereby perpetuates the regime of Curency Board.