External assurance of the materiality process increased by 16%, in line with expectations set out in mandatory reporting requirements. Across all three regions, most reports (83%) were assured at a limited level. Some 87% of reports have external assurance for the majority of material sustainability-related key performance indicators (KPIs) or for the reporting process – a slight (3%) decrease from last year. The majority (83%) apply a limited level of assurance, while 16% have a combination of limited and reasonable assurance, consistent with last year’s observations. There was a decrease in companies reporting reasonable assurance, with only 1% indicating this in 2025. In the Americas and EMEA, no reports have reasonable assurance for the wider scope of material sustainability KPIs, while 3% of reports from APAC indicate this level of assurance. Companies have communicated some obstructions in attaining reasonable assurance, including cost, time constraints and data collection challenges. We expect limited assurance to remain the norm in the future. CSRD mandates that companies have an externally assured materiality process, a requirement that we see playing out this year: 33% of reports reviewed have external assurance for the materiality process, a 16% increase from last year. In line with regulatory expectations, 48% of EMEA reports have an externally assured materiality process. In APAC and the Americas, the data reveals an increase in external assurance of the materiality process (now standing at 5% and 6% respectively). This brings the total percentage of reports indicating an externally assured materiality process to 22% in APAC and 9% in the Americas. Across all regions, the number of reports indicating internal board-level validation of materiality processes is much higher than external assurance, at 68%, a 9% increase from last year. Seeing more board-level validation is an important sign of the integration and strategic use of the outcomes of the materiality process at the executive level. Spotlight External assurance Figure 8: External assurance with breakdown of level of assurance (% of reports) Additional findings Additional findings External assurance External assurance External assurance Limited Limited Limited Combined Combined Combined Reasonable Reasonable Reasonable 2025 2024 2023 Figure 9: Assurance of materiality process (% of reports) 2025 2024 2023 Externally assured Validated by ExCo/board Externally assured Validated by ExCo/board Externally assured Validated by ExCo/board Additional findings Additional findings