The European Food Safety Authority (EFSA) was asked by the European Commission to perform a risk assessment of neonicotinoids, including imidacloprid, as regards the risk to bees, as a follow up of previous mandates received from the European Commission on neonicotinoids. In this context the conclusions of EFSA concerning the risk assessment for bees for the active substance imidacloprid are reported. The context of the evaluation was that required by the European Commission in accordance with Article 21 of Regulation (EC) No 1107/2009 to review the approval of active substances in light of new scientific and technical knowledge and monitoring data. The conclusions were reached on the basis of the evaluation of all authorised uses of imidacloprid other than seed treatments and granules in Europe (including the foliar spray uses as referred to in recital 7 of Commission Implementing Regulation (EU) No 485/2013). The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the submitted studies and literature data as well as any other relevant data available at national level and made available to EFSA, are presented. Missing information identified as being required to allow for a complete risk assessment is listed. Concerns are identified.