This report presents the Education Policy Institute and Renaissance Learning's first assessment of the learning loss experienced by pupils in England as a result of the coronavirus (COVID-19) pandemic. The analysis is based on the results achieved by pupils in the first half of the 2020/21 autumn term (up to and including 25 October 2020) in comparison to pupils in previous years. Star Assessments are frequently used by schools as their baseline assessment for reading and math, and as such the highest number of assessments are conducted during the autumn term. This report is organized into three parts: Part 1 examines the achieved sample sizes; Part 2 examines historic trends in Star Assessments to develop an approach to measuring learning loss; and Part 3 estimates the mean learning loss in reading (for primary and secondary. pupils) and mathematics (for primary pupils only due to small sample sizes in secondary). [This report was prepared by Renaissance Learning and Education Policy Institute on behalf of the UK Department for Education.]