show Abstracthide AbstractTachinidae is the second most species-rich family of Diptera. It is composed of four subfamilies, and all its members have parasitoid habits. We present the first phylogenomic analysis of Tachinidae using transcriptomic data. The analyses are based on 59 species. We constructed four datasets: three using translated data at the amino acid level (100% coverage with 92 single-copy protein-coding genes, 75% coverage with 1304 single-copy protein-coding genes, and 50% coverage with 1890 single-copy protein-coding genes), and one with nucleotide data (75% coverage with 1304 single-copy protein-coding genes). The trees were obtained by analyzing four matrices, and only minor changes were found among them. Overall, our topologies are well resolved, with high node support. Polleniidae is corroborated as a sister group to Tachinidae. Within Tachinidae, our results confirm the hypothesis (Phasiinae + Dexiinae) + (Tachininae + Exoristinae). Phasiinae, Dexiinae, and Exoristinae are recovered as monophyletic, and Tachininae as polyphyletic. Once again, the tribe Myiophasiini (Tachininae) forms a fifth lineage, a clade sister to all the remaining Tachinidae. The Neotropical tribe Iceliini, formerly in Tachininae, is recovered within Exoristinae, sister to Winthemiini. In general, our results are congruent with recent phylogenetic studies that include tachinids, with the important confirmation of the subfamilial relationships and the existence of the fifth lineage of Tachinidae.