Report once, share many: Solving India’s ESG reporting crunch

On the 14th of every month, India’s GST portal does something few ESG frameworks have managed. It takes invoices suppliers have already filed and turns them into GSTR-2B, a read-only statement of input tax credit for each buyer.

The supplier reports once. Every buyer sees the same numbers in the same format, without a single questionnaire.

ESG data needs that design now. One of us advises companies on growth, efficiency and transactions at Prequate Advisory; the other researches and publishes independently on public finance and tax systems. From both seats, the next reporting wave is heading straight for India’s mid-market.

SEBI has set a precise boundary for the value chain

BRSR reporting applies to India’s top 1,000 listed companies. In July 2023, SEBI’s BRSR Core framework asked the top 250 to report on value chain partners covering 75% of purchases or sales, on a comply-or-explain basis.

SEBI then refined the design. Its March 2025 circular defines value chain partners as those that individually make up 2% or more of purchases or sales, and lets a company stop at 75% coverage. Disclosure is voluntary from FY 2025-26, and assessment or assurance of it is voluntary from FY 2026-27. A new leadership indicator also covers green credits generated or procured by the top 10 value chain partners.

India’s largest companies chose the harder audit

Listed India is setting a high bar. A February 2026 KPMG review of 94 NIFTY 100 companies found that every one chose reasonable assurance for its FY 2024-25 BRSR Core data, and none used the lighter assessment route. 57 of the 94 also obtained assurance on wider sustainability data.

That standard will travel. SEBI’s glide path for third-party checks on BRSR Core reaches India’s top 1,000 listed companies in FY 2026-27. Companies that verify their own numbers this carefully will want supplier data that can stand the same scrutiny.

The 2% rule caps the list at 50

Read the 2% test as arithmetic and a useful fact appears. At most 50 partners can each hold 2% of anything, because 50 × 2% is 100%.

So no listed company can have more than 50 in-scope suppliers and 50 in-scope customers. Across the top 250, the ceiling is 25,000 relationships. Real lists will sit below it, because spend spread across many small vendors falls outside the test and the 75% limit lets companies stop early.

That is careful rule-making. It points the request at the partners that matter most and spares the long tail of small vendors.

It also tells us who those partners are. For a company buying ₹10,000 crore of inputs a year, a 2% supplier sells it ₹200 crore, inside the ₹500 crore turnover limit for a medium enterprise. A large buyer’s 2% suppliers will often be mid-market firms.

Europe asks the same firms for carbon data

The EU’s Carbon Border Adjustment Mechanism entered its definitive regime on 1 January 2026. Importers declare 2026 emissions by 30 September 2027 and start buying certificates in February 2027, and a 50-tonne annual threshold now exempts the smallest importers.

The cost picture is better than many feared. A 2026 Sandbag analysis reported by Business Today found that once higher EU steel prices are counted, the net CBAM cost to Indian steel falls from about €762 million to about €79 million, and new low-emission capacity could turn it into a €44 million gain.

The deciding variable is verified plant data. The India-EU trade deal concluded in January 2026 adds cooperation on carbon price recognition and on recognising verifiers. If Indian verifiers are recognised, one verified plant record could serve an Indian listed buyer and a European importer alike.

Seven templates for the same electricity bill

BRSR Core sets 9 attributes, from greenhouse gas, water and energy footprints to employee wellbeing, gender diversity and fair dealing with customers and suppliers. Much of it rests on documents a factory already holds: power bills, fuel invoices, water records and payroll.

The risk for a mid-market supplier is repetition. A firm selling to 5 listed companies and 2 EU importers could receive 7 templates for overlapping numbers, each in a different format and on a different date.

Tax had the same shape of problem, with many buyers needing the same supplier data, and GST answered it with one filing at the source.

Borrow the engine of GSTR-2B

The engine behind GSTR-2B is simple. Data is captured once, at the source, in one standard format, and every counterparty entitled to see it receives it automatically.

A supplier ESG statement would run on the same engine. A supplier files a short annual return on BRSR Core definitions covering energy, emissions, water, waste and workforce safety. Buyers pull it by consent, and plant-level emissions per tonne sit in the same record for EU customers.

Consent comes first. Energy and water data can reveal a supplier’s costs, so each buyer should see only the fields its own reporting needs, and the supplier should see who viewed what.

India already has the people to write the format. The Industry Standards Forum of ASSOCHAM, FICCI and CII wrote the industry standards for BRSR Core that SEBI issued on 20 December 2024.

What policymakers and suppliers can do in 2026-27

• SEBI and the Industry Standards Forum. Publish a short supplier ESG template on BRSR Core definitions, so every listed buyer asks for the same fields in the same format.
• Ministry of MSME. Extend existing MSME support schemes to supplier ESG assessments, starting with firms that sell to the top 250 listed companies.
• Suppliers: start with energy. Power bills and fuel invoices give the energy footprint and much of a factory’s direct and electricity-related emissions.
• Suppliers: treat the data as a sales asset. A buyer that reports on its top partners will value one that arrives with verified numbers ready.

Conclusion: report once, share many times

SEBI has drawn a clear boundary for value chain reporting, and the EU’s carbon border mechanism asks for plant-level data on the same timeline. Both requests land on the same mid-market firms in 2026-27.

A supplier ESG statement built on the GSTR-2B engine, with BRSR Core definitions and an industry-written format, would let each firm report once and share with every buyer.

India taught millions of businesses to file tax data once and let the system carry it. ESG data can travel the same road.

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