The article examines the implementation of Catherine II's provincial reform and aims to ascertain the extent to which the principle of approximate equality of population (from 300 to 400 thousand male souls) declared in the Statute for the Administration of Provinces of 1775 was implemented in determining the boundaries of the new provinces. The article also explores the influence of other factors on the formation of the new system of administrative-territorial division. The research is grounded in the analysis of a spatial model comprising two correlated electronic maps reflecting the administrative division on the eve of the reform and after its completion, based on a wide range of cartographic and statistical sources from that era. The model facilitates the identification of the territories belonging to each of the regions (provinces and guberniyas prior to the reform, namestnichestvos and regions post-reform) and enables a comprehensive reconstruction of the land redistribution process. The maps are studied in comparison with the final data of the IV revision of 1781–1783. The study encompasses the territories where the conventional guberniya, province and uyezd division prevailed prior to the 1775 reform, including Moscow, Novgorod, Arkhangelsk, Saint Petersburg, Smolensk, Nizhny Novgorod, Voronezh, Belgorod, Kazan, Orenburg and Astrakhan guberniyas. The territories comprising Vyborg, Livonia and Estland guberniyas, in conjunction with those regions of Siberia, the territories that were acquired by the initial partition of Poland, and analogous areas where such a division either was nonexistent or was founded on local traditions with notable peculiarities, fall outside the stipulated limits. The analysis indicates an absence of land exchange between the study areas and the outskirts, thereby corroborating the hypothesis that the delineation of these regions aligns with the objectives of the reform proponents. The analysis revealed that the decreed population norm was applied inconsistently when delineating the boundaries of the new namestnichestvos, with significant deviations observed both upwards and downwards from the stipulated norm. The causes of this inconsistency are attributed to the small population of the periphery, the nature of the reform, the abolition of a number of densely populated provinces, the population of which was distributed among neighboring namestnichestvos, and other factors.