The article reveals the specifics of the participation of customs institutions of the Soviet Union in the implementation of the lend-lease program. The authors substantiate the crucial role of state security risk management and the possibility of organizing interaction between countries on an international legal basis in the context of a global aggravation of the geopolitical situation. Certain aspects of Allied supply management based on supply protocols to the USSR and the Treaty with Great Britain on Alliance in the War against Nazi Germany are considered, and the basic principles of lend-lease settlements between the United States of America, Great Britain and the Union of Soviet Socialist Republics are noted. Using the example of the Arkhangelsk and Murmansk customs offices, the contribution of the customs institutions of the Soviet Union to the implementation of the lend-lease program, the process of restructuring their activities in a military manner, the main content of their activities, problems and solutions in wartime conditions are revealed. Attention is focused on the importance of the Northern Route and the volume of Allied aid during the first period of the Great Patriotic War. The data on the volume of assistance from the American Office for Compliance with the Law on ensuring the protection of the United States and statistical data from the Main Customs Directorate of the People\'s commissariat of foreign trade were used. Discrepancies in the data are identified and the need for further research of the lend-lease problem by Russian scientists is shown. The analysis of various approaches to determining the place, role and significance of lend-lease in achieving the victory of the anti-Hitler coalition over nazism is carried out.