Although the familyHalieaceae(OM60/NOR5 clade) is an abundant and cosmopolitan clade widely found in coastal seas and involved in interactions with phytoplankton, a limited number of cultured isolates are available. In this study, we isolated six pure culturedHalieaceaestrains from coastal seawaters and performed a comparative physiological and genomic analysis to give insights into the phylogeny and metabolic potential of this family.