In this study, we investigated bacterial community structure and distribution in the Sargasso Sea and adjacent regions of the North Atlantic between the Bahamas and the Northeastern U.S. at the surface and at depth using high-throughput amplicon DNA sequencing. Based on preliminary findings and available literature, we hypothesized that there would be no geographic barrier to bacterial communities among sampling regions. We also sought to investigate the potential for dispersal barriers on the basis of depth within the euphotic zone, contributing to community dissimilarity between surface communities and communities in the DCM, and to determine significant environmental factors which may select for characteristic dominant communities.