Since GST is implemented suddenly the impact about it cannot be measured with the registered persons. This study is done to find out the result because for every new reforms impact is an important matter. The present research is exploratory in nature. The study tries to find the registered persons in GST. With a sample size of 402 respondents, the study has been conducted within Coimbatore city. The sampling method was simple random sampling and the data collection tool was a structured questionnaire. Result of the study has a positive impact on GST reforms and also medium knowledge among the registered persons about GST reforms.