Threats of increased differentiation across regions, which have caused inefficient spatial development, are progressively coming into the scientists’ focus. By and large, a peripheral region is unlikely to take the place of the center. In the Urals1 , the Sverdlovsk oblast has long been the center and stayed ahead of its neighbours in terms of socioeconomic performance. Our previous research revealed a phenomenon called ‘synchronisation of economies’. Accordingly, the Chelyabinsk oblast in many instances repeats the trends of the Sverdlovsk oblast, but remains at the periphery. In this regard, studying the differentiation between the two economies becomes a relevant issue. The research aims to construct long-term trends of differentiation between regions using the case of the Sverdlovsk and Chelyabinsk oblasts. The theories of spatial development, including the theory of cumulative growth, constitute the methodological basis of the research. Applying the methods of statistical comparison and times series analysis, the study interprets the data published by Russia’s Federal State Statistics Service (Rosstat), the Unified Interdepartmental Statistical Information System (UISIS), and generated by FIRA PRO information analytics system (OOO “First Independent Rating Agency”). The author proposes a method for assessing differentiation across regions based on 12 indicators. The findings demonstrate that for 2001–2020, the variation between the regions in terms of GRP per capita (in 2001 prices) has increased, whereas in terms of wages in prices of the same year it decreased. In relation to the outsider region, the Sverdlovsk oblast has kept its position in terms of the real GRP per capita compared to the Chelyabinsk oblast, which is approaching the outsider. At the same time, for 2001–2020, both regions have become closer to the leader. With regard to the real wages, the positions of the regions have nearly equalized, the ‘superiority’ over the outsider has decreased.