The objective of this study was to assess the economics of the post-weaning phase and performance of Nellore calves born to dams that received protein concentrate supplementation during the final trimester of pregnancy. This research was organized into two phases: Phase I entailed a 90-day supplementation period for the dams in the last third of their pregnancy, and Phase II spanned from the birth of the calves to their weaning at 240 days. Twenty multiparous Nellore cows, subjected to fixed-time artificial insemination (FTAI), were divided into two groups: unsupplemented (US) and supplemented (SP), each comprising 10 animals. Statistical analysis was performed using an analysis of variance and the F-test with a significance level set at 0.05, within a completely randomized design. Among the parameters examined, only the total feed cost (US = BRL41.09 vs. SP = BRL112.22, P = 0.0001), effective operating cost (US = BRL872.51 vs. SP = BRL943.64, P = 0.0001), total operating cost (US = BRL925.51 vs. SP = BRL951.64, P = 0.0001), and total cost (US = BRL925.51 vs. SP = BRL996.64, P = 0.0001) were significantly affected by protein concentrate supplementation during the last third of pregnancy. Therefore, it can be concluded that while protein concentrate supplementation in the final stages of pregnancy does not influence the performance or morphological traits of calves, it does lead to increased feed and labor expenses. However, these increases do not negatively impact economic viability rates.