BRSR Core reasonable assurance is the higher assurance bar, applying extensive testing and a positive conclusion, that the Securities and Exchange Board of India requires over the nine assurable ESG attributes of BRSR Core, phased in by market-capitalisation rank across the top 150, 250, 500 and 1,000 listed entities from FY 2023-24 to FY 2026-27.
What BRSR Core reasonable assurance means
BRSR Core is the subset of key, assurable KPIs carved out of the wider Business Responsibility and Sustainability Report, introduced by SEBI circular dated 12 July 2023. It specifies KPIs grouped under nine ESG attributes: Green-house Gas (GHG) footprint, Water footprint, Energy footprint, Embracing circularity (waste), Enhancing Employee Wellbeing and Safety, Enabling Gender Diversity in Business, Enabling Inclusive Development, Fairness in Engaging with Customers and Suppliers, and Open-ness of business. Reasonable assurance is the higher assurance bar, involving extensive testing, larger samples, evaluation of internal controls and a positive conclusion, as distinct from limited assurance. Intensity ratios use revenue adjusted for Purchasing Power Parity (PPP) for global comparability.
Who must obtain it, and by when
Filing of the wider BRSR became mandatory for the top 1,000 listed entities by market capitalisation from FY 2022-23. The reasonable-assurance requirement then phases in by market-capitalisation rank across four financial years.
| Market-cap rank | Reasonable assurance from |
|---|---|
| Top 150 | FY 2023-24 |
| Top 250 | FY 2024-25 |
| Top 500 | FY 2025-26 |
| Top 1,000 | FY 2026-27 |
The assurance provider must be free of any conflict of interest, and must not sell products or provide non-audit or non-assurance services to the entity or its group.
The 2025 assessment-or-assurance option
SEBI circular dated 28 March 2025 renamed the approach column from “Data and Assurance” to “Data and Assessment or Assurance”, clarifying that an entity may obtain either reasonable assurance or a third-party assessment carried out under standards developed by the Industry Standards Forum (ASSOCHAM, CII and FICCI) in consultation with SEBI. India-specific KPIs identified for assurance include:
- job creation in small towns
- gross wages paid to women as a percentage of total wages
- openness of business (spending on related parties)
Preparing the underlying data file and readiness for independent assurance is advisory work; the assurance or assessment itself is performed by independent accredited third parties. Structured groundwork appears in the ESG guide.
Sources: SEBI BRSR Core framework circular (12 July 2023) · SEBI easing circular (28 March 2025)