More Global Companies Seek Assurance on Sustainability Reporting, Study by IFAC, AICPA & CIMA Shows

• The percentage of companies engaged in sustainability reporting remained unchanged at 98%
• 73% of companies obtained assurance on at least some of their sustainability disclosures
• Greenhouse gas emissions remain the most widely assured category of sustainability information

NEW YORK, May 12, 2025 /PRNewswire/ -- Almost 3-in-4 of the largest global companies sought assurance on some aspect of their sustainability disclosures, according to an updated report from the International Federation of Accountants (IFAC) and AICPA & CIMA. The study marks the fifth annual benchmark that now includes 2023 data.

Seventy-three percent of large companies from G20 countries obtained assurance on their sustainability disclosures in 2023, up from 69 percent the previous year, according to the report, The State of Play: Sustainability Disclosure and Assurance, (Five-Year Trends and Analysis, 2019-2023). Five years ago, that number stood at 51 percent. Most of the assurance then and now is of limited scope.

Audit firms—as opposed to consultants or other service providers—continue to lead (55 percent) in providing assurance on sustainability disclosures by large global companies, with broad variations country to country. Audit firms' overall share of the market declined from 58 percent in 2022, although there are mitigating factors for the drop, including:

• Consolidation of reports – In the European Union, where audit firms historically provide the majority of sustainability assurance, firms began issuing a single assurance report instead of a series of separate ones, lowering the raw number of reports issued, albeit for  an increased number of assurance clients.
  
  
• Consultants and non-audit firm service providers are more likely to issue multiple greenhouse gas-related assurance reports (for example, an average 2.5 assurance reports were generated per company in South Korea during 2023).
  
  
• When companies obtain assurance for the first time, they typically focus on greenhouse gas-related information and start by engaging other service providers who specialize in that area.

The report notes the increased use of audit firms over the prior year in several major markets in 2023, including Singapore (+6 percentage points), South Africa (+4), the United Kingdom (+5) and United States (+5). In the latter instance, audit firms' share of sustainability assurance rose from 23 percent to 28 percent.

"Auditors have extensive education requirements, adhere to strict independence rules and possess a deep and holistic view of an organization's business, processes and risk profile," said Susan Coffey, CPA, CGMA, the CEO of public accounting for AICPA & CIMA  "That makes them ideal candidates to perform sustainability assurance engagements, and we're seeing many boards and audit committees endorsing that view as corporate reporting matures."

More than three-quarters of companies now report sustainability information with financial disclosures in annual or integrated reports. Organizations that include sustainability information with their annual or integrated reports overwhelmingly use their statutory auditor to provide assurance over those disclosures.

"The largest global companies have responded well to voluntary systems of sustainability reporting and assurance, driven by investor demand," said IFAC Chief Executive Officer Lee White. "With new global standards in place, regulators now have the toolkits to move from voluntary to mandatory disclosures over time, which we expect will further drive high-quality, consistent and comparable sustainability-related information for the investing public and all stakeholders. IFAC and our members, including AICPA & CIMA, remain committed to supporting this shift—advancing trust, good governance, and global alignment in sustainability disclosure, united in shaping a future where sustainability information earns the same level of trust as financial reporting."

Among other highlights of the updated study:

• Almost all companies (98 percent) report some information on sustainability. This is unchanged from last year.
  
  
• Use of sustainability information in annual reports continues to rise. Some 44 percent of companies included it in their annual report, up from 18 percent five years ago.
  
  
• Five jurisdictions had double-digit increases in sustainability assurance in 2023: Hong Kong, Indonesia, Mexico, Russia and Saudi Arabia.  

About the Study

IFAC and AICPA & CIMA partnered to understand sustainability reporting and assurance practices on a global basis by capturing reports containing environmental, social and governance (ESG) information in 22 jurisdictions. Some 1,400 companies were reviewed—100 from each of the largest six economies, with 50 companies reviewed in the remaining 16 jurisdictions. The current report includes data from 2019-2023. Full methodology is available in the study. 

About AICPA & CIMA, together as the Association of International Certified Professional Accountants

AICPA & CIMA, together as the Association of International Certified Professional Accountants (the Association), advance the global accounting and finance profession through our work on behalf of 597,000 AICPA and CIMA members, candidates and registrants in 188 countries and territories. Together, we are the worldwide leader on public and management accounting issues through advocacy, support for the CPA license, the CGMA designation and specialized credentials, professional education and thought leadership. We build trust by empowering our members, candidates and registrants with the knowledge and opportunities to be leaders in broadening prosperity for a more inclusive, sustainable and resilient future. 

About the International Federation of Accountants

IFAC, by connecting and uniting its members, makes the accountancy profession truly global.

IFAC member organizations are champions of integrity and professional quality, and proudly carry their membership as a badge of international recognition.

IFAC and its members work together to shape the future of the profession through learning, innovation, a collective voice, and commitment to the public interest.

SOURCE AICPA & CIMA