Purpose: The purpose of this study is to analyse the impact of financial intermediation and regulatory frameworks on financial deepening and economic growth in Lesotho, utilizing data from 2003 to 2022. The objective is to explore the relationships between selected financial and economic indicators and assessing their influence on financial deepening. Methodology: This study utilized secondary time series data, which poses challenges regarding authenticity and reliability since it was collected by external parties. However, these concerns were addressed by using data from reputable global agencies like the IMF, World Bank, and the Central Bank of Lesotho’s annual report from 2003 to 2022. The analysis was conducted using the Ordinary Least Squares (OLS) regression method. Findings: The findings highlight the complex role of financial intermediation and regulatory frameworks in shaping financial deepening and economic growth. Higher cash reserve ratios and treasury bill rates negatively affect financial deepening by reducing liquidity and increasing credit costs. However, increased commercial bank deposits with the central bank positively contribute to financial stability and deepening. Moderate inflation also fosters financial deepening by raising the nominal value of financial assets. While ATMs per capita enhance financial access and growth, an increase in bank branches per capita shows inefficiencies, underscoring the need for effective infrastructure and service delivery. Unique Contribution to Theory, Policy and Practice: The study suggests that policymakers should adjust cash reserve requirements, monitor credit expansion to avoid over-lending, and improve banking infrastructure. It highlights the need for careful interest rate management and promoting financial innovation to enhance market depth.