The MAFIA project aims to quantify the active vertical flux of carbon by migrant organisms in the ocean. The main sampling effort within this project was an oceanographic cruise carried out in 2015 during which samples were collected in 13 locations across the tropical and subtropical Atlantic: from 13ºS, off the Brazilian coast, to 27ºN, south of the Canary Islands. The cruise section crossed distinct oceanic environments, from oligotrophic gyres to the highly productive northwest African upwelling system, as well as the equatorial divergence zone. The water column was extensively sampled, from the surface to 3500 m depth.