The LOCATE (Land Ocean CArbon TransfEr) project in the UK consists of measurements of dissolved organic carbon (DOC), nutrients, temperature, salinity, alkalinity and sediment in rivers and estuaries combined with a terrestrial model to predict the future evolution of the land ocean carbon flux. LOCATE samples identify the amount of organic carbon, washed from soils, enters the oceans, with emphasis on estuaries and coastal waters. The LOCATE project integrates knowledge and skills across NERC terrestrial, freshwater and marine research centres to transform the UK’s ability to measure, model and predict land-ocean fluxes in a changing environment. LOCATE is a collaboration between the National Oceanography Centre (NOC), the Centre for Ecology and Hydrology (CEH), the British Geological Survey (BGS) and the Plymouth Marine Laboratory (PML). LOCATE is funded by the Natural Environment Research Council (NERC) from 2016 until 2021. The estuarine and oceanographic data are held by the British Oceanographic Data Centre (BODC), the river data are held by the Environmental Information Data Centre (EIDC).