Telecommunication sector has grown over last decade while transforming behavioral intentions. New entrants are exploring these behavioral intentions to attract more customers. The aim of this study is to investigate the mediating effect of customer satisfaction in telecom industry on service quality, brand image and customer retention relationship. Furthermore, it identifies the key determinants of customer retention related to telecom service providers. A fully structured questionnaire survey was conducted to collect data from 310 mobile users. Non-probability sampling technique was adopted for data collection. Regression analysis and Sobel test technique were practiced to analyze the data. The result showed that customer satisfaction mediates the relationship between service quality, brand image and customer retention. Moreover, this study found that service quality, brand image and customer satisfaction are the strongest predictors of customer retention in telecom industry of Pakistan. Therefore, to gain customer loyalty, organizations should focus current-users and target-users by providing sterling service quality