Abstract Purpose: This paper examines Norwegian companies’ perceptions of the transition to widespread mandatory sustainability reporting (CSRD) and related frameworks (ESRS) initiated by the EU. Their perceptions are investigated by elucidating the effect it will have on companies’ practices, while covering possible areas of resistance. Method: The paper is based on a cross-sectional interview study with 13 Norwegian companies, which are all defined as large undertakings according to Directive 2013/34/EU. The analysis follows an inductive approach and is conducted utilizing a thematic analysis. Findings: The CSRD and ESRS are considered comprehensive, but necessary to improve sustainability performance of affected companies. Norwegian companies describe a need for resources and competencies within sustainability reporting, more evident in smaller-sized companies. Respondents claimed, inter alia, that streamlining of processes would ensure compliance and optimal prioritization. The transition was regarded as feasible, given that resources, competencies, and systems facilitate it. Research limitations/implications: This study’s findings extend prior research on mandatory sustainability reporting, by examining sustainability reporting practices in light of this widespread mandate. In terms of limitations, varying knowledge among interviewees placed a heavier burden of interpretation on the interviewers. Value: This study contributes to the ongoing discussion of widespread mandatory sustainability reporting. In addition, we believe that our findings will provide useful insights that can aid in improving the quality of sustainability reports.