The efficiency of operation of motor vehicles with a DMC (Permissible Laden Mass) <3.5 tonnes is considered. These are vehicles belonging motor vehicles of category N1, usually referred to as delivery vehicles. The results of observations on the implementation of transport orders in 7 transport companies from the MŚP (Small and Middle-size Companies) sector were used to conduct the effectiveness analysis. The research group covered 24 vehicles that implementation transport orders in the urban zone and in the immediate vicinity of the city. Information was collected on a monthly basis.During the analysis of economic efficiency the income measures (absolute and relative) were used. The calculations were carried out using the model of the vehicle operation process in the form of a neural network, in which a set of 12 input variables and 3 output variables were taken into account. Using the Statistica 13.3 computer program and defining the group and factors describing the process of implementation of individual transport tasks, the developed neural network model enabled searching for the impact of selected operational factors on the economic efficiency of N1 category cars.The calculations showed a significant impact of the number of vehicle days in a month, the weight of the load, as well as the time of year. The obtained calculation results showed the specific features of the impact of the number of working days on revenue in a transport company. The increase in the number of working days favors the increase in income in a limited way, and this restriction depends, among others since the time of year