This study examined the influence of internal auditing practices on financial accountability in Wakiso District Local Government, Uganda. Internal auditing is widely regarded as a key mechanism for promoting financial accountability in public institutions, yet its contribution in Ugandan local governments remains under-examined. The study investigated how audit independence, audit planning and scope, internal control review, and audit reporting and follow-up relate to financial accountability. A cross-sectional survey design with a mixed-methods approach was adopted, and data were collected from 175 respondents comprising internal auditors, finance and accounting staff, and management using structured questionnaires and interviews. Descriptive statistics, exploratory factor analysis, Pearson correlation, and structural (path) analysis were used. Factor analysis confirmed the construct validity of the internal auditing dimensions, which loaded onto coherent factors and explained 68.5% of the variance. The results revealed a strong positive and significant relationship between internal auditing practices and financial accountability (r = 0.68, p < 0.01), with the practices jointly explaining 66.0% of the variance in financial accountability (R² = 0.660). Audit reporting and follow-up (β = 0.32) and audit independence (β = 0.30) emerged as the strongest path predictors. The study concludes that internal auditing significantly enhances financial accountability and recommends strengthening audit reporting and follow-up, audit independence, and internal control review.