In this paper we review the benefit-cost analyses (BCAs) made to support applications for authorisations under the EU’s REACH Regulation on hazardous chemicals. Experiences from over 100 cases suggest that there are a number of informational and methodological challenges to overcome in these BCAs. In particular, we find that many REACH applicants have had problems explaining the societal relevance of the regulatory impacts expected to affect them and other market actors. Adapting the framework for regulatory impact assessment proposed by Dudley et al. [(2017). Consumer’s Guide to Regulatory Impact Analysis: Ten Tips for Being an Informed Policymaker. Journal of Benefit-Cost Analysis, 8, 187–204], we discuss these impacts from a welfare economics perspective and make suggestions on how to improve current practices in BCA applied to chemicals risk management. From this discussion we then distill a number of topics that deserve more attention in applied BCAs under the REACH Regulation.