Partitioning primary production into contributions from surface and subsurface phytoplankton communities, is useful for understanding the primary production directly visible by, and hidden from, passive ocean colour remote sensing, and for understanding the new primary production that occurs below the mixed layer. Here we combine a model, that partitions a vertical profile of phytoplankton biomass in two communities of phytoplankton (surface and subsurface), with measurements collected on two Atlantic Meridional Transects, of photosynthesis-irradiance incubations (at surface and deep chlorophyll-a maximum), and profiles of light, backscattering and chlorophyll-a, to quantity surface and subsurface primary production through the Atlantic Ocean.