Production of aviation biofuels has been strongly encouraged by the volatility of oil prices and environmental concerns. Brazilian society, companies, and government are taking a step forward in the production of renewable jet fuel from biomass feedstocks largely available in the territory. This study evaluated the use of different feedstocks (sugar crops, oil crops, and lignocellulosic biomass) for co-production of biojet fuel and higher value-added products in a biorefinery platform. The co-production of biofuels and biochemicals in a biorefinery context was demonstrated to be economically feasible. The main cost drivers of such a platform are feedstock biomass cost, selling price of the biochemicals, investment costs, and key process-inherent parameters such as conversion yields, obtained fermentable sugars, or oil content in the feedstock. Sugarcane was the most promising feedstock for a biorefinery in the region of Minas Gerais, while soybean was the most promising feedstock for a biorefinery in the region of Rio Grande do Sul, despite its higher uncertainty. Succinic acid was the most promising chemical intermediate for biopolymers industry due to its relatively high market value, unique market opportunity as a substitute of conventional petrochemicals, and forecast for future growth. Ethanol-to-jet (ETJ) and hydro-processed esters and fatty acids (HEFA) were the most attractive biojet fuel production routes in the present study. Scenarios for co-production of biofuels and biochemicals in Brazil present large uncertainties and high financial risk, mainly due to the use of second-generation feedstocks, and the introduction of new technologies and products.