Corporate restructuring through mergers and acquisitions (M&A) has emerged as an important strategic approach for organizations seeking sustainable growth, improved competitiveness, and enhanced financial performance. The present study examines the impact of corporate restructuring on the fundamental financial performance of organizations by analyzing the merger between HDFC Ltd. and HDFC Bank Ltd. The research is based on secondary data collected from the annual reports of HDFC Bank Ltd., HDFC Ltd., Moneycontrol, and other reliable financial sources. The study evaluates the financial performance of the merged organization by comparing the pre-merger and post-merger periods using key financial indicators such as Revenue, Net Profit, Return on Equity (ROE), and Earnings Per Share (EPS). Statistical tools including Comparative Analysis, Descriptive Statistics, Financial Ratio Analysis, and the Independent Samples t-test were employed to assess the significance of changes in financial performance following the merger. The findings reveal substantial improvements in Revenue and Net Profit after the merger, indicating enhanced operational efficiency, profitability, and business expansion. Although Return on Equity showed a marginal decline due to the enlarged equity base, the statistical analysis confirmed a significant difference between the two periods. Earnings Per Share improved during the post-merger period but did not exhibit a statistically significant difference. Overall, the study concludes that the HDFC Ltd.–HDFC Bank Ltd. merger positively influenced the organization's fundamental financial performance and strengthened its long-term financial position. The findings provide valuable insights for corporate managers, investors, researchers, and policymakers regarding the effectiveness of mergers and acquisitions as a strategic tool for creating sustainable shareholder value and organizational growth.