Purpose This study aims to examine the simultaneous effect of variations in the Capital Adequacy Ratio and Credit Risk of Islamic banks of the Gulf Cooperation Council under the influence of the Basel III regulations using an innovative approach. Design/methodology/approach This approach highlights the critical importance of the Basel III reform in preserving the stability of the regional and international financial sector in the Gulf Cooperation Council and globally by examining the complex dynamics between Capital Adequacy Ratio and Credit Risk and their interaction under regulatory constraints. The annual reports and financial performance of 26 Islamic banks were analyzed over the period 2013–2021. Findings The findings highlight the critical importance of the Basel III reform in preserving the stability of the regional and international financial sector in the Gulf Cooperation Council and globally by examining the complex dynamics between Capital Adequacy Ratio and Credit Risk and their interaction under regulatory constraints. The annual reports and financial performance of 26 Islamic banks were analyzed over the period 2013–2021. Originality/value The insights from findings help define effective strategies to manage and mitigate Credit Risk while strengthening solvency under Basel III prudential supervision. Policymakers, regulatory authorities and banking institutions can optimize the management of Credit Risk and create a robust and stable financial environment for Islamic banks.