Background: In this paper, the problem of sustainability of investment activity in the direction of the high yield investment program is considered. In these financial instruments, large amounts of money are accumulated, consisting of contributions from the vast majority of the population. For example, pension funds inherent in most developed countries, insurance institutions, etc., can be indicated. Accordingly, the social significance of their activities and the impact on the quality of life of all segments of the population increase. Methods: This article outlines the methods and results aimed at the digital transformation of methods for forecasting long-term institutional investments. The authors use the method of mathematical modeling of the dynamics considering that the sustainability calculation must assume that the life cycle of citizens providing contributions is limited. The parameters of the distribution of the duration of the accumulation phase over the array of people and the time of life in the subsequent period are known. For mathematical modeling, the researchers divide the players by the time they have been present on the market. Results: The authors have developed a mathematical model in the form of a set of algorithms for calculating the sustainability of long-term institutional investments with reference to life quality indicators. Conclusions: The need to develop a methodology for assessing sustainability is dictated by the increased role of digital technologies and the ability to receive the most relevant information for analysis online.