From 150 to 1,000: what BRSR Core assurance means for India's mid-cap companies this year

SEBI's BRSR Core is a set of key ESG indicators that listed companies must have independently checked. The requirement has widened every year, by market capitalisation:

• FY 2023-24: the top 150 listed companies
• FY 2024-25: the top 250
• FY 2025-26: the top 500
• FY 2026-27: the top 1,000

SEBI's circular of 28 March 2025 also lets companies choose a third-party assessment instead of assurance. The same circular made value-chain disclosures voluntary from FY 2025-26, with voluntary assessment or assurance of them from FY 2026-27. Companies that do report value-chain ESG data must say what share of their purchases and sales those partners cover.

What changes for companies ranked 501 to 1,000

For many of these companies, FY 2026-27 is the first year an assurance or assessment provider will ask to see the evidence behind their BRSR Core figures: greenhouse gas emissions, energy, water, waste, and the social indicators in the Core.

An outside check looks at more than the reported number. It asks where each figure came from, who approved it, and whether the calculation can be repeated.

Three things to settle before the provider arrives

1. A source for every figure. Each BRSR Core indicator should trace back to a meter reading, an invoice or a record, not only to a spreadsheet total.
2. One version of the truth. The figure in the filed report, the working file and the evidence should match, with every change recorded.
3. Named owners. Someone at each site should be able to explain how their figures were produced and checked.

Our BRSR readiness checklist lists what to have in place before a BRSR filing, a BRSR Core assessment or assurance, and the XBRL filing. It is free and needs no account.