UK statistics agencies (ONS, StatsWales, NRScotland and NISRA) produce mid-year population estimates (MYE), national population projections (NPP), and subnational population projections (SNPP), by age and gender. Mid-year estimates and subnational population projections are at local authority district (or equivalent) geography; national projections are produced for England, Wales, Scotland and Northern Ireland respectively. At the time of writing (June 2018), mid-year estimates are available from 1991 to 2016. Subnational population projections typically have a 25-year horizon and in most cases cover the period 2016-2041. National projections have a longer horizon, extending from 2016 to 2116. The datasets are published online in different places and in different formats, depending on the originating agency. The data may require significant preprocessing/reformatting before it can be used programmatically and, crucially, reproducibly. Population projection variants (e.g. high fertility) are extremely useful for scenario analyses and a number of population projection variants are available at national scale. However, the availability of variants at subnational scale is patchy at best. This python package (Smith 2018) aims to unify the retrieval of UK-wide data, providing consistent interfaces for each of the three (MYE, SNPP, NPP) datasets.