Supplier Carbon Data: China, Vietnam and India

Buying teams sourcing from China, Vietnam and India often ask suppliers for the same carbon data spreadsheet regardless of where the factory sits. That wastes effort, because each country’s regulatory infrastructure now produces genuinely different starting points. China’s national emissions trading scheme generates verified, facility-level data for a growing share of heavy industry suppliers. Vietnam has moved from paper-based inventories to a live pilot carbon exchange. India’s carbon market remains mostly a plan, with steel targets still in draft. Matching what a supplier can credibly provide against what your own CBAM, CSRD or SBTi reporting needs is the real task behind “getting supplier carbon data” — and it looks different in each market.

China: ETS data is becoming a usable starting point

China’s Ministry of Ecology and Environment expanded the national emissions trading scheme to cement, steel and aluminium in 2025, adding roughly 1,500 companies and taking total coverage to around 8 billion tonnes of CO2e — about 15% of global emissions 1. The first compliance deadline for these sectors fell at the end of 2025, covering 2024 emissions, with a two-phase rollout: a 2024–2026 familiarisation period focused on data quality, then tighter rules from 2027 1.

For buyers, the practical upshot is that covered suppliers now file monthly emissions reports with supporting documentation, subject to a three-tier review at national, provincial and municipal level 1. Where direct measurement is not feasible, suppliers may still rely on pre-approved default values, so a covered supplier’s ETS filing is not automatically primary, facility-specific data — it is worth asking whether reported figures are measured or defaulted before treating them as verified. Aluminium smelters also now report perfluorocarbon and hexafluoroethane process emissions alongside energy-related CO2, which matters for buyers calculating product carbon footprints rather than only site-level totals.

Vietnam: inventories give way to a trading exchange

Decree 06/2022, as amended by Decree 119/2025, set mandatory greenhouse gas inventory obligations for a growing list of facilities. Decree 29/2026 has now operationalised trading for three pilot sectors: 34 thermal power plants, 25 iron and steel facilities and 51 cement plants, with pilot quotas of 243 million tonnes CO2e for 2025 and 268 million tonnes for 2026 2. Facilities outside these three sectors, including most textile, footwear, furniture and electronics suppliers, currently fall under the inventory obligations of Decree 06/2022 rather than the trading scheme.

That distinction matters for buyers: a Vietnamese steel or cement supplier inside the pilot has an incentive to produce robust, audited emissions data because it now has a market value. A garment or furniture supplier outside the pilot is still working from inventory reporting alone, without the same verification pressure. Ask which regime a given facility sits under before assuming a Vietnamese supplier’s numbers carry the same assurance as a Chinese ETS filing.

India: a market still being built, not yet delivering data

India’s Carbon Credit Trading Scheme (CCTS) released draft compliance targets for the steel sector in July 2026, still subject to public consultation and formal notification. The Bureau of Energy Efficiency has said it expects trading under the Indian Carbon Market to begin by October 2026, but this is a stated expectation rather than a binding deadline 3. India is separately negotiating with the EU and UK for CCTS to be recognised as a qualifying carbon pricing scheme under CBAM’s Article 9, and for Indian accredited verifiers to be accepted for CBAM compliance — an outcome that would let exporters offset EU certificate costs against carbon prices already paid at home 3.

Until that recognition is settled, Indian steel and aluminium suppliers have limited regulatory push to produce verified emissions data, so buyers should expect to fund or commission primary data collection directly rather than assume it will arrive through domestic reporting duties, as our earlier guide to India CBAM verification sets out in more detail.

What “good” supplier data actually looks like

Whichever country a supplier sits in, the same quality questions apply. The Partnership for Carbon Transparency’s Pathfinder Framework, now in its second version, standardises how companies calculate and exchange product-level, primary-data-based emissions across a value chain, and adds a verification and assurance roadmap so buyers can compare data quality across suppliers on a common basis 4. Requesting data in a Pathfinder-aligned format, rather than a bespoke spreadsheet, makes it easier to aggregate figures from suppliers across China, Vietnam and India without reconciling incompatible methodologies later.

The GHG Protocol’s own Scope 3 Standard revision, still at the progress-update stage rather than public consultation, points the same way: the draft restricts allocation of aggregated corporate-level supplier data to genuinely homogeneous suppliers, and proposes a new requirement to disaggregate reported emissions by data type — primary, modelled or default — to make the proportion of real primary data visible 5. Building supplier requests around this distinction now avoids a rework once the revised standard is finalised.

Matching data quality to your own reporting duty

How much precision you actually need depends on which framework is pulling the data. Under CBAM’s definitive regime, which started on 1 January 2026, importers bringing in more than 50 tonnes a year of covered goods — cement, iron and steel, aluminium, fertilisers, electricity and hydrogen — must hold authorised CBAM declarant status, declare embedded emissions annually and surrender certificates priced against EU ETS allowance auctions, calculated as a quarterly average in 2026 and a weekly average from 2027 6. That is a hard, transaction-level data requirement with no “undue cost or effort” relief, as our CBAM emissions data guide covers.

CSRD reporting is more forgiving. EFRAG’s proposed simplifications to ESRS E1 explicitly permit secondary and estimated data for value chain metrics under an “undue cost or effort” principle, removing the previous hierarchy that favoured direct data collection, though this relief does not extend to omitting Scope 3 emissions altogether 7. The revised standard is expected to apply from financial year 2027, with early adoption possible in 2026, while current reporters continue under the original ESRS Set 1 until the Commission adopts the final delegated act. SBTi’s Corporate Net-Zero Standard Version 2.0 sits in between: it makes scope 3 targets mandatory for larger companies but optional for smaller ones, asks companies to prioritise categories that represent 5% or more of emissions, and explicitly recognises data traceability and market constraints as legitimate limits on what can be achieved immediately 8.

In practice, this means CBAM-exposed steel, aluminium and cement purchases justify commissioning primary, verified data regardless of cost, while general Scope 3 categories reported under CSRD or SBTi can often rely on good secondary data and default factors, reserving primary data requests for your highest-emitting supplier relationships.

A practical request-to-supplier checklist

Before sending a data request, it helps to confirm four things with each supplier: which domestic scheme, if any, covers their facility (China ETS, Vietnam’s pilot exchange or inventory regime, or India’s still-forming CCTS); whether their reported figures are measured or based on default values; whether they can supply data in a Pathfinder-aligned, product-level format rather than only a site-level total; and who verified the figures, and against which standard. For CBAM-relevant suppliers, add a fifth question: can they support an authorised declarant’s annual embedded-emissions declaration with transaction-level detail, not just an annual site figure.

Common data gaps and how to handle them

The most frequent gap is a supplier reporting a corporate-level or site-level average when you need a product-specific figure — common among diversified manufacturers in all three countries. Rather than rejecting the data, ask whether the supplier’s product lines are similar enough for allocation to be defensible, in line with the GHG Protocol’s homogeneity test, and document that judgement. A second common gap is unverified self-reported figures presented as if they were audited; treat these as a starting point for engagement rather than a number to publish. Where no usable data exists at all — still common for smaller Vietnamese and Indian suppliers outside pilot schemes — a transparent secondary-data estimate, clearly labelled as such, is preferable to a data request that stalls the relationship indefinitely.

Getting started

None of this needs to be solved in one request. Start with the suppliers that matter most to your CBAM exposure or your largest Scope 3 categories, ask the four verification questions above, and build toward Pathfinder-aligned reporting over successive purchasing cycles rather than demanding it immediately. If you would like help mapping which of your China, Vietnam or India suppliers sit under which regime and building a realistic data collection plan, talk to our team.