The aquaculture sector is the fastest growing food production industry, with sea bass and sea bream consisting important exporting goods in the Mediterranean region. This work presents results of a life cycle assessment of Mediterranean sea bass and sea bream, based on primary data collected from a Greek producer. The system boundary included fish feed production and the rearing operation, as well as the packaging and delivery processes, which were neglected in preceding literature studies. The life cycle inventory developed addressed previous data gaps in the production of Mediterranean aquaculture species. Comparison to preceding studies revealed differences on the production inventories and identified methodological choices leading to variability. Packaging and delivery processes were found to contribute approximately 40% towards the global warming score. The production of both sea bass and sea bream was shown to come with high eutrophication impacts occurring from the rearing stage. The feed production was identified as the most environmental impact intensive process throughout the life cycle. Sea bass came with lower environmental impacts per unit live mass, which was reversed when the species were compared on a protein basis. The replicable and transparent model presented here, contributes towards the more accurate quantification of the environmental impacts associated with Mediterranean aquaculture species and supports efforts aiming to promote environmental protection through dietary change.