Aquaculture is expected to play an important role in the transition towards healthy and sustainable diets, requiring dietary changes towards products with lower environmental footprints in ways that address dietary needs. Farmed Atlantic salmon accounts for 2% of global aquaculture, with productivity growth factors, such as research investment, credited with creating a high-value, globalized food commodity. However, its contribution to sustainability and nutrition goals remains unclear, and factors underlying consumer demand, such as marketing work, have been overlooked. We inspect the rise of farmed salmon in the UK, using key stakeholder interviews to understand the role of various actors (e.g. industry, retailers) in ‘making’ farmed salmon markets. Interviewees identified retailer strategies, such as labelling, and consumer-facing promotion efforts, such as health benefits, as key demand-growth factors underlying farmed salmon sales. Using data on UK seafood markets, we assess the views of interviewees, finding that farmed salmon is the most consumed aquatic food; however, it is less popular than other animal-source foods and is primarily consumed by affluent households. Our analyses discuss how market-making efforts by industry and retail actors have shaped consumer demand by promoting salmon as an accessible, nutritious and sustainable product. Accreditation and labelling have helped to develop perceptions of health and sustainability, despite farmed salmon being comparable in nutrient profile to other aquatic foods and having long-standing environmental impacts. Market-making insights could be used to enhance demand for other aquatic foods in ways that target dietary gaps by supplying affordable and sustainable products, such as mussels.