The aim was to obtain bacterial genomes from Atlantic salmon (Salmo salar) gut samples, to be used as a reference for further meta-omics studies. The study is part of the ImprovAFish (Improving aquaculture sustainability by modulating the feed-microbiome host axis in Fish) project. In commercial-scale trials, Atlantic salmon were fed with different feed additives, including a promising functional ingredient (beta-mannan) that is known to promote beneficial microbiota in livestock. Hindgut content was collected from dissected salmon at different developmental stages, in fresh- and saltwater. Metagenomic DNA was extracted from these samples (I) directly, (II) after enrichment of microbial DNA through host DNA depletion, and (III) after enrichment of microbial cells through filtration, differential centrifugation, and fluorescence-activated cell sorting.