The data consist of daily maps of volumetric soil moisture predicted by a model based on a network of cosmic-ray neutron sensors (COSMOS-UK), the National River Flow Archive (NRFA) and remotely-sensed data. Maps cover the UK and Ireland at 2 km resolution in the Ordnance Survey National Grid (OSGB) projection. Maps are produced in near-real time, lagging by about one week. Data are available from early 2016 to 2023, on a daily basis. The model was calibrated on a network of cosmic-ray neutron sensors (COSMOS-UK) and remotely-sensed soil moisture data. A key parameter was estimated from the national-scale spatial pattern in the catchment response to rainfall seen in the National River Flow Archive (NRFA) data. Precipitation and humidity data to drive the model came from the Met Office High Resolution Numerical Weather Prediction model (NWP-UKV) which incorporates the C-band rainfall radar network. The maps have a variety of uses in hydrology and elsewhere, for example as inputs to ecosystem models of greenhouse gas exchange, where soil moisture affects numerous processes. The modelling was carried out as part of UK-SCAPE Virtual Survey Lab, and the NERC project "Detection and Attribution of Regional Emissions (DARE-UK)". There are some gaps in the time series of meteorological and remote sensing inputs, and data are unavailable for these days. The NRFA data are only available for Great Britain, so estimates in Ireland and continental Europe will be less accurate. Full details about this dataset can be found at https://doi.org/10.5285/5aa8c5b4-4485-4954-b5c3-18d937a418f7