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Estrogenic signaling is an important focus in studies of gonadal and brain sexual differentiation in fishes and vertebrates generally. This study examined variation in estrogenic signaling (1) across three sexual phenotypes (female, female‐mimic initial phase [IP] male, and terminal phase [TP] male), (2) during socially‐controlled female‐to‐male sex change, and (3) during tidally‐driven spawning cycles in the protogynous bluehead wrasse (Thalassoma bifasciatum). We analyzed relative abundances of messenger RNAs (mRNAs) for the brain form of aromatase (cyp19a1b) and the three nuclear estrogen receptors (ER) (ERα, ERβa, andERβb) by qPCR. Consistent with previous reports, forebrain/midbraincyp19a1bwas highest in females, significantly lower in TP males, and lowest in IP males. By contrast,ERαandERβbmRNA abundances were highest in TP males and increased during sex change.ERβamRNA did not vary significantly. Across the tidally‐driven spawning cycle,cyp19a1babundances were higher in females than TP males. Interestingly,cyp19a1blevels were higher in TP males close (~1 h) to the daily spawning period when sexual and aggressive behaviors rise than males far from spawning (~10–12 h). Together with earlier findings, our results suggest alterations in neural estrogen signaling are key regulators of socially‐controlled sex change and sexual phenotype differences. Additionally, these patterns suggest TP male‐typical sociosexual behaviors may depend on intermediate rather than low estrogenic signaling. We discuss these results and the possibility that an inverted‐U shaped relationship between neural estrogen and male‐typical behaviors is more common than presently appreciated.