Treasury Single Account (TSA) is one of the critical reforms set in Sierra Leone to consolidate government funds into a unified system and ensure greater transparency in public finance management. This study discusses the role of TSA in resource mobilization, its economic benefits, and its limitations. Corruption in MDAs has been a long-standing hindrance to Sierra Leone's development and has undermined efforts to improve the socio-economic well-being of citizens. The study adopted a mixed-methods approach using qualitative, quantitative, and descriptive analyses based on primary and secondary data. One hundred copies were distributed to TSA implementing MDAs and supervising agencies, which comprise the Ministry of Finance and Bank of Sierra Leone. It is also necessary to state that other tools were used: questionnaires and document analysis. Microsoft Excel and SPSS were used for data to produce statistical output, such as frequency distribution, percentages, and graphs. Findings indicate that TSA has had impacts on improving fiscal discipline and the predictability of budget and increasing fiscal space on the MDAs' practices. This study's results recommend further strengthening both the legal and regulatory framework in the system process of operating TSA, optimally and efficiently through the government institution. Future outcomes depend on sustained reforms targeted to ensure system strengthening and timely resource allocation to support effective public financial management, hence the promotion of the socio-economic development of Sierra Leone.