This study examines the impact of the Government Integrated Financial Management Information System (GIFMIS) on capital expenditure management in Nigeria, focusing on its role in addressing corruption within the procurement system. The specific objectives include assessing variations between budgeted and actual expenditures in the administrative, economic, and social sectors pre- and post-GIFMIS implementation. Utilizing an ex-post facto research design, secondary data from the annual reports of the Accountant-General of the Federation (2001–2022) were analyzed. The period was divided into pre-GIFMIS (2001–2011) and post-GIFMIS (2012–2022) phases, enabling a comparative assessment of the system’s impact across the three sectors. Paired t-test analysis, integrated with regression techniques, was used to account for temporal fluctuations and sector-specific factors. Findings revealed that the pre-GIFMIS era exhibited no statistically significant variations between budgeted and actual expenditures in all sectors, with the administrative sector showing a mean difference of X_1i=1.15138 (p>0.05, t=21.244), the economic sector X_1i=4.18820 (p>0.05, t=3.313), and the social sector X_1i=0.18947 (p>0.05, t=2.278). Conversely, the post-GIFMIS era demonstrated significant variations across all sectors: the administrative sector recorded X_1i=3.12325 (p<0.05, t=26.833), the economic sector X_1i=0.84540 (p<0.05, t=1.598), and the social sector X_1i=0.05297 (p<0.05, t=0.602). These findings suggest that GIFMIS has enhanced financial accountability and transparency, but the observed disparities show that there are issues with matching budgeted and actual spending. Therefore, it can be concluded that GIFMIS has been instrumental in changing the face of financial management in the country especially with the post implementation period revealing a lot of improvements in the areas of transparency and accountability. However, the differences between the budgeted and actual expenses indicate that there is a need for further enhancement in the use of the system. In order to overcome these challenges, the government should enhance the budget planning, monitoring and implementation in all sectors. Continued training of personnel and the incorporation of performance evaluation mechanisms will also improve GIFMIS’s efficiency in the fight against corruption in Nigeria’s procurement process.