Customer satisfaction forms the foundation of any business success, as it leads to service reuse, brand loyalty and positive word of mouth. This study has been conducted as a survey. Convenient sampling method has been applied on a sample of 300 enterprises that have been using online tax payment services of the Tax Department of Ho Chi Minh City. The research model parameters include: (1) Information and system quality, (2) Time efficiency, (3) Confidentiality of information and transactions, (4) Support service / customer service, (5) Helpful awareness, (6) Trust in tax authorities. The results show that confidentiality of information and transactions has the strongest impact. Trust in tax authorities and Helpful awareness impact goes second. Next is time efficiency and support service/customer service. Finally, the Information and system quality is ranked the last one since it has the lowest beta coefficient.