The Indian mutual fund industry has experienced significant expansion in recent years. Systematic Investment Plans (SIPs) have become the preferred investment option for individual investors due to their disciplined, flexible, and long-term wealth creation potential. The factors impacting adoption, risk attitude, investment knowledge, and satisfaction levels are the main emphasis of this study, which assesses how retail investors in the Thoothukudi area behave with regard to SIPs. 110 retail investors provided primary data via a structured questionnaire as part of a descriptive research strategy.  To investigate the association between demographic factors and SIP investing behavior, the data were analyzed using percentage analysis, descriptive statistics, and Analysis of Variance (ANOVA). The data show that characteristics such as low initial investment, regular investment discipline, fund performance, fund house reputation, and fintech-based advising support all have a beneficial impact on SIP adoption, with no significant differences across age groups.  Furthermore, the study finds no significant association between income level and investors' risk attitude or knowledge of SIPs, demonstrating a consistent level of awareness and behavioral orientation across income groups.  The findings indicate that retail investors in Thoothukudi engage in consistent and sensible SIP investment behaviour, driven by post-pandemic financial planning requirements and increasing access to digital investment platforms.  The study provides valuable insights for mutual fund managers, financial advisors, and governments looking to improve investor education campaigns and encourage retail investors to participate in SIPs for the long term.