Sustainability Assurance Services Market To Approach $5 Billion In 2031

Growing expectations for accurate and reliable sustainability data – from regulators, investors and other stakeholders – are driving increased demand for assurance services. In our 2026 market size and forecast report, Verdantix forecasts that global market spend on sustainability assurance services will grow from over $1.8 billion in 2025 to over $4.9 billion in 2031. What are some of the key takeaways from our research?

• Growth in the sustainability assurance market was slower than predicted.

  In our 2023 market size and forecast, we predicted that the sustainability assurance market would grow to over $2.6 billion by 2025, which is approximately $835 million more than our current estimate of the 2025 market. This is largely due to differences in scope between the two reports and shifting market conditions. In 2026, the updated model excludes pre-assurance services (which were covered in our 2023 model) and focuses only on limited and reasonable assurance engagements. At the same time, regulatory delays – such as postponed CSRD timelines in Europe and the SEC’s paused climate rule in the US – have softened demand. Broader economic uncertainty has also constrained sustainability budgets, leading some firms to delay assurance investments.

• Regulations are a key driver, but not the only one.
  While regulatory requirements remain the primary catalyst for assurance adoption, organizations are increasingly motivated by other factors. These include mitigating greenwashing risks, improving confidence in sustainability data and aligning sustainability disclosures with financial reporting standards. As sustainability data become more central to business strategy, firms are seeking assurance to enhance credibility, support decision-making and meet rising stakeholder expectations.
  

• Europe leads the market, but Asia will see the fastest growth.
  Europe accounted for the largest share of the sustainability assurance market in 2025, with spend driven by frameworks such as the SFDR and the CSRD. Although growth in the region will be more measured going forwards, Europe will retain its leading position due to regulatory scale and ongoing investor pressure. In contrast, Asia is expected to experience the fastest growth, driven by the expansion of regulations aligned with ISSB standards and increasing demand for globally comparable disclosures.
  

• Industries with complex supply chains will see the highest growth, due to increasing regulatory pressures.
  Industries with complex supply chains – particularly manufacturing, and wholesale and retail trade – are expected to have the highest growth rates between 2025 and 2031. Firms in these sectors will be directly impacted by extended producer responsibility (EPR), zero-waste initiatives and pressure from supply chain requirements, as well as increased pressure to validate claims regarding recycled content and carbon footprinting.

To learn more about how and why spend on sustainability assurance services will increase, see Market Size And Forecast: Sustainability Assurance Services 2025-2031 (Global).