This study examined the impact of external auditing on the financial performance of Ssubiryo Financial Services over a five-year period from 2015 to 2020. External auditing plays an important governance role for microfinance institutions like Ssubiryo by promoting accountability and transparency. However, the precise effects of mandatory external audits on key metrics had not been empirically assessed. A mixed methods explanatory research design was employed. Quantitative data was obtained from Ssubiryo's audited financial statements for 2015-2020 to analyze trends in return on assets, portfolio at risk ratios, operational self-sufficiency, and financial expense ratios using SPSS. Qualitative data was also gathered through interviews with a sample of 19 managers and staff who had worked at Ssubiryo for at least three years. Interview discussions explored perceptions of impacts from the external audit process. Document review supplemented these findings. The results indicated that post-audit, return on assets increased from an average of 2.3% to 3.1% while portfolio at risk ratios declined, suggesting reduced credit risk exposure. Operational self-sufficiency also improved to safely above 100%, signifying adequate cost coverage. Trend tests revealed significant positive changes in most indicators following the initial 2015 audit. Interview themes recognized strengthened oversight of lending practices, internal controls and financial reporting requirements attributed to audits. The management should enhance verification of accounting data and all financial transactions or statements to improve accountability and acknowledgement of organisation funds and resources hence enhancement of accountability, quality service delivery and economic efficiency.