The Atlantic mackerel, Scomber scombrus, is a common pelagic species distributed in the Northern Atlantic Ocean and in the temperate waters of the Mediterranean Sea and the Black Sea down to about 200 m.  Northeast Atlantic mackerel defines the mackerel in the region from ICES Division subareas 1–8 and 14, and in Division 9.a. Spawning areas are equally widely distributed but catches are attributed to three spawning components by area – North Sea (4, 3a), Western (6, 7, 8 a,b,d,e) and Southern (8c, 9a). Fish from Southern and Western areas have been shown to migrate to the North Sea, Norwegian Sea, and Baltic Sea after spawning where they become indistinct from other components. Given the uncertainties in the determination of a stock structure, an assessment unit is considered in the Northeast Atlantic and adjacent waters (Brunel et al. 2017)(ICES 2019). A recent workshop was developed to clarify the uncertainty regarding mackerel stock structure, conclusions are that directed genetics, tagging, otolith chemistry investigations; ongoing surveys; catch data; fisher perspective; and preliminary modeling studies all failed to support the three-component concept for NEA mackerel, recommending that the current ‘headline advice’ based on a single-stock assumption should continue (ICES 2024).