This study evaluates the economic capital levels for Iranian banks and analyzes their behavior under various macroeconomic shocks by developing a Dynamic Stochastic General Equilibrium (DSGE) model that incorporates banking sector heterogeneity and macroeconomic shock transmission mechanisms. A comprehensive DSGE framework was constructed and calibrated using Iranian macroeconomic and banking data. The model implementation utilized Dynare software to analyze impulse response functions across technology, liquidity, and monetary policy shock scenarios, with particular emphasis on capital adequacy dynamics, bank bankruptcy and exit possibilities, and effects on economic welfare and financial stability.

Simulation results indicate that current capital levels of Iranian banks are insufficient for achieving financial stability and welfare maximization, requiring increases to higher levels, that exceeding Basel III regulatory minimums to maintain adequate resilience against macroeconomic volatility and prevent bank bankruptcy and exit. Technology shocks generate expansionary effects on output, consumption, and investment variables while improving economic welfare, whereas liquidity shocks create contractionary pressures reducing these key economic indicators and welfare levels. Interest rate shocks produce moderate and largely temporary effects across macroeconomic variables, with limited long-term impact on economic welfare and minimal influence on bank bankruptcy probability.

The shock analyses demonstrate the critical importance of macroeconomic conditions in bank capital management decisions, economic welfare preservation, and bank exit prevention, with liquidity shocks showing the most substantial explanatory power for capital requirement variations. The study contributes to both theoretical understanding and practical application by extending DSGE modeling to incorporate banking sector capital dynamics, bankruptcy mechanisms, and welfare effects within an emerging market context, thereby offering a more comprehensive framework for economic capital determination.

Our findings suggest that Iranian banks need to maintain higher capital levels to provide adequate stability and risk absorption capacity for Iranian banks under diverse economic shock conditions.