This record links data outputs of the NERC Historic Droughts project. The datasets comprise reconstructed hydro-meteorological time series of potential evapotranspiration (PET), river flow and ground water levels from the 1890s to 2015 for the UK. It also includes a number of drought indicators derived from these hydro-meteorological parameters: Standardised Precipitation Index (SPI), Standardised Streamflow Index (SSI) and Standardised Groundwater level Index (SGI). Other data outputs of Historic Droughts (archived elsewhere) include newly digitised historic precipitation and temperature data, used in the creation of the SPI and PET data listed here. The Historic Droughts project aimed to develop an interdisciplinary understanding of drought from a range of different perspectives. The hydro-meteorological datasets listed here were used to produce timelines of past droughts which were brought together with an inventory of historic drought information from a range of other sectors (media, legislation) which is archived elsewhere.