Carbon and nitrogen content (g per g soil) of the free-light fraction (LF), the occluded particulate fraction (OF), the mineral associated organic matter fraction (MAOM), the particulate organic matter (POM = LF+OF), soil organic carbon (SOC), total soil nitrogen (TN) and soil organic matter (SOM from loss-on-ignition) of 100 topsoil samples (0-15 cm) from the UKCEH Countryside Survey 2019/20 are presented. Associated and historic soil and vegetation data is available through the Countryside Survey data collection: https://catalogue.ceh.ac.uk/documents/2069de82-619d-4751-9904-aec8500d07e6 Full details about this dataset can be found at https://doi.org/10.5285/29cd5386-bc2e-4d70-a6a5-0d7dc7513dc6
