Comparative analysis of two models for predicting residual resource of polymer composite, one proposed by specialists from RS Technologies Inc and the other proposed by Institute of Oil and Gas Problems SB RAS (Russia), was carried out to obtain service life of composite poles for power transmission lines manufactured by RS Technologies Inc (Canada) for cold climate of Republic of Sakha (Yakutia). Models are based on experimental studies of strength of materials during accelerated and full-scale climatic tests. The difference lies in the presence of parameters of climatic zone and test methods in the first model, while the second model considers changes in physical and mechanical properties and structure of materials during aging under conditions of full-scale exposure and accelerated climatic tests. Comparison of results of predicting the durability of fiberglass products in cold climate of Yakutsk (Russia) according to Institute of Oil and Gas Problems SB RAS model and similar products in Calgary (Canada) climate (the closest in terms of climate conditions) according to RS Technologies Inc model showed the same results. Service life of composite support material was approximately 120 years with specified level of permissible decrease in characteristic property index of 75% of the original.