This study investigates the impact of tax planning strategies on the financial performance of Small and Medium Enterprises (SMEs) in Rivers State, Nigeria. In a volatile economic environment where tax burdens can significantly affect business sustainability, strategic tax planning has become a critical financial management tool. The study specifically examined the effect of three tax planning strategies income shifting, tax deferral, and investment in tax-deductible assets on two financial performance indicators: net profit margin and return on total assets (ROA). A descriptive survey research design was adopted, and data were collected from 172 respondents of selected registered SMEs through structured questionnaires. Data were analyzed using descriptive statistics, Pearson correlation, and multiple regression analysis. The findings revealed that all three tax planning strategies had a statistically significant and positive effect on both net profit margin and ROA. Among them, investment in tax-deductible assets exhibited the strongest influence on financial performance. The regression model showed that tax planning strategies jointly explained over 50% of the variation in SME profitability. The study concludes that effective tax planning enhances the financial health of SMEs by improving profit margins and asset efficiency. It recommends that SMEs integrate tax planning into their financial decisions, engage professional tax advisors, and adopt tax management technologies. The findings also call for government policy reforms to provide targeted tax incentives and education programs for small business operators. This research contributes to the growing body of literature advocating tax planning as a key driver of SME sustainability in developing economies.