The hide, larder and carpet beetles (Coleoptera: Dermestidae) are a family of mainly scavenger beetles, with numerous species such as the khapra beetle , the black carpet beetle and the hide beetle, being widely recognised as serious economic pests of stored products and museum collections. In this study we examined and sequenced mitochondrial genomes of 477 dermestid specimens, representing all subfamilies and 90% of tribes and subtribes. Our study provides the most comprehensive, taxonomically verified and vouchered resource of mitochondrial reference sequences and occurrence records of pests and their relatives, enabling eDNA surveys, metabarcoding and molecular species identification. It also reconstructs the phylogeny of Dermestidae based on molecular and morphological data for the first time, thereby providing robust phylogenetic hypotheses for a stable classification system from family to genus-level. Accordingly, a revised classification of Dermestidae with formal nomenclatural changes is proposed, recognising six subfamilies: Orphilinae, Trinodinae, Trogoparvinae subfam. nov. (type genus Trogoparvus Háva, 2001), Dermestinae, Attageninae and Megatominae. Attageninae is strongly supported and includes the monogeneric Adelaidiini and polygenic Attagenini. Former subgenera of Attagenus Latreille are elevated to generic level. The largest clade, Megatominae, is confirmed as monophyletic and is divided into three tribes. Megatomini is divided into three subtribes: Megatomina, Orphinina subtribe nov. and Trogodermina. Within the economically important lineage Trogodermina, Trogoderma is delimited to contain Holarctic species including the Khapra beetle T. granarium, while a Southern Hemisphere clade is here recognised as Eurhopalus Solier in Gay. A revised classification of the extant genera of Dermestidae is also provided.