The economic development of the off-shore territories of the Arctic zone is characterized by certain advantages and risks associated with the geographical location. Territorial formations of the ASRF have unequal economic structure and different levels of economic development, harsh climatic conditions, preferential economic and legal regime, etc. Territories develop unevenly: some territories have steady economic growth, others are characterized by processes of stagnation, still others are characterized by degradation and devastation. The object of the research is the coastal territories of the Arctic zone of the Russian Federation, and the subject is the process of their economic development. The aim is to study the process of development of coastal cities in the Arctic zone of the Russian Federation, on the example of the Karelian Arctic and the Arkhangelsk region. The study is based on the use of hardware for comparative analysis and assessment of indicators of coastal territories' development. The novelty of the study is the use of the rank method and the calculation of σ-variance coefficient, which allow to determine the presence of regional heterogeneity in its dynamics in the context of coastal cities of the ASRF, on the example of the Karelian Arctic and the Arkhangelsk region. The results determined the presence of a gap between the urban settlements under consideration. The assessment of the inequality of some indicators demonstrates the trend of coastal cities to convergence, other indicators in the context of coastal cities steadily diverge. Large urban settlements break away from other cities of the European North. Small urban settlements of coastal location - Kem, Kandalaksha, Belomorsk - are characterized by a low level of development. The findings may serve as the basis to form the strategic and program documents, and can be also used as additional material, while analyzing the coastal cities of the AZRF and the dynamics of their development.