Allergen cross-contact and unintended allergen presence (UAP) are a significant challenge for food operators. The aim of this document is to translate the findings of the Expert Group on ‘Food Allergen Quantitative Risk Assessment (QRA)’ into a Guidance document which provides tools and approaches to help harmonize the data gathering process for food allergen risk assessments and therefore aid with their implementation. This Guidance aims to promote consistency in documentation, decision making and the application of allergen QRA. The purpose of this Guidance is not to take an allergen labelling or risk management decision for the user, but rather is intended to help them decide when allergen QRA is appropriate or necessary, and how to decide if it can actually be performed and, if it is to be undertaken, what is the most suitable methodology. Any resulting risk management measures or actions planned should be checked to assure compliance with local legislation before implementation. As a part of the development of this Guidance and in order to strengthen the overall document, feedback was sought and received from stakeholders from the food industry, food safety authorities, academia, patients’ organisations and other research organisations/consultants (see Appendix A (Remington, Baumert et al. 2022)). The intended audience is mainly industry wishing to understand and conduct food allergen risk assessments, and potentially QRA. However, it should be noted, that this guide could also be useful for others, including official control agencies. Training videos for this Guidance will be made available after its publication and can be found here.