Sathish, K. Santhosh kumar, KJ Naveen, V.JeevananthamThis research paper refers to the study with the diverse population of Chennai, Tamil Nadu. The researcher of this article believes that the mass of population includes more middle or low income groups in Chennai. Tamil Nadu consists of a mix of all types of income groups. The study uses an in-depth literature review to identify factors that drive behavior change. The literature reveals factors related to switching costs, better customer support services, network coverage, advertising, etc. to change customer behavior. The researchers identify the industry's problem that if one company makes money, the other necessarily loses a customer. The number of network providers is increasing and requires strong competition. The enhancement of technology has led to cheaper growth of the mobile phone industry. The objectives are to ascertain the best market share of telecommunications providers, the population's attitude to change, the most crucial influence in influencing change behavior and the purchase of a SIM card. Research methodology The research methodology used