In order for producers to choose the correct alternatives among different forage sources, it is necessary to know the production cost as well as the factors that most impact cost formation. Therefore, the objective was to survey the production cost, the economic impact, and the productivity losses of corn silage. To this end, seven silage production systems located in the state of São Paulo and 11 systems in the state of Minas Gerais were used. The data collection period was from September 2015 to May 2016. The effective operating cost was composed of expenses for soil analysis, lime, diesel fuel, fertilizers, seeds, herbicides/insecticides, plastic sheeting, inoculants, and miscellaneous expenses. The total cost of producing corn silage in the 2015/16 season was R$ 317.30 per ton of dry matter or R$ 104.71 per ton of green matter. Inputs (seeds, fertilizers, and pesticides) were the most significant cost items, followed by harvesting and ensiling, planting and cultural practices, and soil preparation. Sensitivity analysis showed that the cost was 1.92 times higher considering different yields and loss percentages, with the lowest cost being R$ 81.57 and the highest R$ 157.32.
