© 2009, BioMed Central Ltd. Halogeometricum borinquense Montalvo-Rodríguez et al. 1998 is the type species of the ge-nus, and is of phylogenetic interest because of its distinct location between the halobacterial genera Haloquadratum and Halosarcina. H. borinquense requires extremely high salt (NaCl) concentrations for growth. It can not only grow aerobically but also anaerobically using ni-trate as electron acceptor. The strain described in this report is a free-living, motile, pleomor-phic, euryarchaeon, which was originally isolated from the solar salterns of Cabo Rojo, Puer-to Rico. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the halobacterial genus Halogeometricum, and this 3,944,467 bp long six replicon genome with its 3937 pro-tein-coding and 57 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.