EFSA has asked the Panel on Plant Protection Products and their Residues to prepare guidance on the establishment of the residue definition for dietary risk assessment. The residue definition for risk assessment is used by risk assessors to evaluate the potential risk of dietary intake of residues resulting from the application of a pesticide. This document guides the complex process of identifying the pertinent residue components that should be considered for dietary risk assessments of chemical active substances. Specifically, the document provides directions for determining the metabolites that require hazard identification and characterisation using scientific tools and methods ((quantitative) structure-activity relationship ((Q)SAR), read-across, threshold of toxicological concern (TTC)) and available data in combination, and for developing an appropriate testing strategy for these compounds. Further, for activities within the remit of the guidance document the terms 'potency' and 'toxicological burden' for consumers are defined and decision criteria established for the selection of the residue components that should be included in the residue definition for dietary risk assessment. In order to support the decision process it is recommended to make use of all information available, including mechanistic understanding, and to present detailed information on toxicity and exposure for every single metabolite and on the uncertainties connected to the proposed residue definition. The guidance document is complemented with three practical case studies demonstrating the applicability of the proposed decision scheme