In the context of the global transformation of the economic space, economic entities become integrated into various kinds of associations and alliances. These processes make it emphatically relevant to improve approaches to assessing and forecasting the competitiveness of such large companies, taking into account the changing conditions of their internal and external environment. Previously developed approaches required a certain revision and appropriate improvements. The purpose of the study is to improve methodological tools and assess the competitiveness of large copper companies at the present stage and in the medium term. Based on the analysis of approaches to assessing and ensuring the competitiveness of economic entities, it was revealed that today the vast majority of these approaches do not take into account the changing conditions of competition and the increased influence of factors reflecting these changes. The article proposes an improved scientific and methodological approach to assessing and forecasting the competitiveness of large companies, which includes four major blocks: the formation of scientific and methodological principles for conducting research; development of methodological tools for multifactorial assessment of the company's competitiveness; optimization of investment projects for the development of the company; formation of predictive strategies for the development of the company associated with the provision of long-term competitive advantages. As part of the approach - a method for multifactorial assessment of the competitiveness of large companies - has been developed. It provides for the consideration of additional factors and their priority, as well as a significant correction of the basic comparison model. A scenario-based methodological approach has been developed to predict the indicators of competitiveness of large companies using economic and statistical modeling, taking into account the specifics of the company's activities. Methodological developments were tested in relation to the Ural Mining and Metallurgical Company against the background of large global companies operating in the same field. The assessment of the level of current competitiveness of companies was carried out in the period 2010–2020; the forecast of competitiveness indicators was made for the period through to 2025, which made it possible to assess post-pandemic development trends from the standpoint of the competitiveness of the companies in question. Based on the results of the study, generalizing conclusions are formulated.