The Business Responsibility and Sustainability Report (BRSR), introduced by India's Securities and Exchange Board in 2021, replaced the earlier Business Responsibility Report. Starting in FY 2022–23, SEBI mandated the top 1,000 listed companies to disclose ESG performance across nine principles aligned with the National Guidelines on Responsible Business Conduct.
SEBI rolled out assurance requirements in phases. In 2023, "reasonable assurance on BRSR Core" became mandatory for the top 150 entities. By 2024, this expanded to the top 250 companies, requiring either assessment or assurance. The scope continues expanding through FY 2026–27, eventually covering the top 1,000 listed entities.
BRSR Core comprises key performance indicators across nine ESG attributes, including greenhouse gas emissions, energy intensity, water withdrawal, waste management, employee welfare, pay equity, and workforce safety metrics.
"Assurance represents the process of validation and verification of information by an independent qualified professional," while "assessment involves evaluation and verification against established criteria." Two assurance levels exist: reasonable assurance (highest level) and limited assurance (less extensive review).
Eligible assurance providers include Chartered Accountants or other professionals with sustainability expertise. SEBI recognizes globally accepted standards including ISAE 3000, ISSA 5000, SSAE 3000, and SAE 3410.
Assurance readiness requires robust ESG data, processes, and controls enabling independent verification without data gaps or methodological inconsistencies. Key pillars include engagement management, data governance, disclosure quality, internal controls, and Board oversight.