The paper touches upon the issue of improving the efficiency of the process of providing services for the payments payment by the population through a distributed system of instant payments. Improving the efficiency of the service delivery process is achieved by supporting decision-making managers, system administrators at three stages of the service delivery process: creating a service, making a payment, and evaluating the service effectiveness. A scheme of management of rendering services process in the system of instant payments, a block diagram and an algorithm of the DSS work describing decision support in the system in question are presented. The process of instant payment system operation was formalized, which allowed developing a distributed system architecture and software based on web services technology. In order to describe the network services, it is proposed to use WSDL using the SOAP protocol and the UDDI interface, which will ensure the interoperability of software systems regardless of platform, as well as the ease of development and web services debugging. Thus, load testing of the instant payment system software was carried out and its reliability was evaluated on the basis of La Padula, Jelinsky-Moranda and Mills models.