Smicridea McLachlan, 1871, is the richest genus of Hydropsychidae in the New World, with its subgenus Smicridea (Smicridea) being the most diverse, comprising 145 species. However, immature stages of only 13% of these species have been described. In Brazil, only five of 29 species of S. (Smicridea) have documented immature stages. To fill this gap, we describe and illustrate the larva and pupa of S. (Smicridea) erecta Flint, 1974. Using the metamorphotype method, we associated adults with their immature stages. Larvae of S. erecta are characterized by ten dark brown oval muscular scars on the posterior region of the frontoclypeus, arranged in a boomerang shape, and a convex and entirely crenulate anterior margin. The pupa exhibits pairs of hook plates exclusively on the abdominal terga of segments II–VI. This study adds to the understanding of Smicridea (Smicridea), making Smicridea (Smicridea) erecta the sixth species in Brazil and the twentieth globally with documented immature stages.