In this paper, a method for calculating critical electric energy price and critical daily distance traveled in an electric vehicle (EV) is proposed based on the life cycle cost theory. The life cycle cost of an EV and its equivalent internal combustion engine vehicle (ICEV) are determined by considering initial investment cost, carbon emissions tax, fuel cost, and maintenance. The use of EVs will be profitable if the price of electrical energy is lower than the critical electrical energy price. The difference between the critical energy price and the present value of electrical energy per kWh is considered as the profit of purchasing an EV. On the other hand, the daily distance traveled by customers is one of the most effective parameters for determining the critical price of electrical energy, the life cycle cost and the choice of EV. Furthermore, the sensitivity analysis of the life cycle cost model is performed for four different scenarios, in which the carbon emissions and its costs are calculated in real time. The results indicate that the profitability of each EV is different and applying the actual carbon emission tax increases the critical price of electrical energy by 8.5%. Moreover, the evaluated EVs can be selected based on the analysis of daily distance traveled and EV charging pattern. The charging pattern of an EV during different hours of a day can reduce the critical distance approximately 40% compared to the peak price of electrical energy.