Supplier Decarbonisation: A 90-Day Pilot Plan for Procurement Teams

A 90-day supplier decarbonisation pilot should test one question: can your procurement team turn supplier carbon data into a decision that reduces emissions? Pick one or two high-emission categories and a small group of suppliers where you have leverage. Spend the first 30 days scoping and estimating, the next 30 collecting supplier data and assessing sites, and the final 30 agreeing reduction actions and writing them into commercial terms. At day 90, decide whether to scale, redesign or stop, based on evidence rather than enthusiasm.

Most programmes fail because they try to cover every supplier at once, not because the idea is wrong. For many companies, Scope 3 is the bulk of the footprint. The SBTi notes that supply chain emissions are on average 11.4 times larger than a company’s direct emissions 3. A tightly scoped pilot is the quickest way to learn what works in your categories, with your suppliers and inside your procurement processes.

What the pilot is for

Set the objective before choosing suppliers. A good pilot delivers four things:

• A tested data process: what you asked for, what suppliers actually provided and how long it took.
• An improved baseline for the pilot categories: moving from spend-based estimates to supplier-specific data where it matters.
• At least one agreed reduction action per engaged supplier: an energy audit, a renewable electricity plan, a material change or a process fix.
• A procurement mechanism: a tender criterion, contract clause or supplier-review item that makes carbon part of commercial decisions.

It is not a pilot’s job to produce a complete, assured Scope 3 inventory or to hit a reduction target in three months. Setting those expectations early protects the programme from being judged on the wrong measures.

Before day one: team and scope

Name a procurement owner, not just a sustainability sponsor. Category managers hold the supplier relationships and the commercial levers, so the pilot needs their time. Add a sustainability or carbon-accounting lead for methodology, and someone who can speak with suppliers in their language if the pilot covers Asian manufacturing.

Then agree the pilot boundary:

Decision	Recommended approach
Categories	One or two categories that rank high in a spend-based screen and where the team has sourcing decisions coming up
Suppliers	A small group, typically a handful to around a dozen, mixing strategic suppliers with at least one smaller one
Geography	Keep it narrow enough that one person can hold direct conversations with every supplier
Budget	Allow for supplier support, such as co-funded energy audits, as well as internal time
Success criteria	Written down before day one and signed off by the procurement owner

Days 1–30: screen, select and prepare

Build a first estimate. Use the GHG Protocol Scope 3 Standard as the accounting reference 1. For purchased goods and services, a spend-based estimate is enough to rank categories and suppliers at this stage. The GHG Protocol’s calculation guidance describes the move from spend-based and average-data methods towards hybrid and supplier-specific methods as data improves 2. Record which method you used for each line so improvements can be tracked later.

Select the supplier group. Rank suppliers in the pilot categories by estimated emissions, then filter for leverage (your share of their business, contract timing, relationship strength) and readiness (existing carbon data, certifications, prior requests from other customers).

Prepare the ask. Draft a short data request covering energy use by source, production volumes, refrigerants and any existing carbon footprint work. Translate it where needed. Explain why the data is requested, how it will be used and how confidential information will be protected.

Check external drivers. If any pilot category involves iron, steel, aluminium, cement or fertilisers imported into the EU, align the data request with CBAM requirements, which have applied since 1 January 2026 6. Our guide to CBAM data from Asian suppliers covers what is needed.

Days 31–60: engage suppliers and assess sites

Hold kick-off meetings, not webinars. A call with each supplier’s management, with the category manager present, signals that the request is commercial and not a box-ticking exercise. Explain what’s in it for the supplier: lower energy costs, a stronger position in future tenders, and data they can reuse with other customers.

Collect and review data. Expect gaps. Common problems include missing sub-metering, incomplete refrigerant records and footprints calculated on inconsistent boundaries. Classify each data point as supplier-specific, estimated or default, and note where it came from.

Assess the sites that matter most. For the largest or most carbon-intensive suppliers, a structured factory-level assessment, on site or remote, will surface reduction opportunities faster than a questionnaire. It should cover energy use by process, heat sources, electricity sourcing, compressed air, refrigerants and material inputs. Our factory-level supplier carbon assessment checklist sets out what to cover.

Use standard exchange formats where possible. If suppliers already calculate product carbon footprints, ask for them in a format aligned with the PACT Methodology, which WBCSD updated to Version 3 in June 2026 to support product-level data exchange across supply chains 5.

Days 61–90: agree actions and embed them in procurement

Agree one to three actions per supplier. Prioritise measures the supplier controls and can start quickly: an energy audit, compressed air leak repair, heat recovery, a rooftop solar feasibility study, a renewable electricity procurement plan, or a lower-carbon material specification. For each action, record the owner, timeline, expected emissions effect (estimated, not promised) and any support you are providing.

Decide how you will share costs. Some actions pay back through energy savings; others need buyer support. Options include co-funding audits, longer contract terms, volume commitments or accepting a price adjustment for lower-carbon material. Do not promise savings you have not estimated with the supplier.

Change at least one procurement process. The pilot only proves something if carbon affects commercial outcomes. Choose one concrete change:

• add carbon data and a reduction plan as a scored criterion in the next tender for the pilot category;
• include data-sharing and review clauses in a contract renewal;
• add carbon progress to the quarterly business review agenda.

Update the baseline. Replace spend-based estimates with supplier-specific data where you now have it, and document the change in method. Be careful not to report the difference as a reduction: a better number is not the same as lower emissions.

Measuring the pilot

Track a short set of indicators and report them honestly:

Indicator	Why it matters
Supplier response rate and time to respond	Tests whether the ask is realistic
Share of pilot-category emissions covered by supplier-specific data	Shows data-quality progress
Number of agreed actions with an owner and date	Shows whether engagement produced commitments
Procurement processes changed	Tests whether carbon has entered commercial decisions
Internal time spent per supplier	Needed to plan the cost of scaling
Supplier feedback	Identifies friction before you roll out

The day-90 decision

End the pilot with a short decision paper for procurement and sustainability leadership. It should cover:

1. What worked and what did not, with evidence from the indicators above.
2. The cost of scaling: internal hours, supplier support budget and any tools needed.
3. Recommended next scope: which categories and suppliers to add, and in what order.
4. Target alignment: how the programme supports any Scope 3 or supplier engagement target. The SBTi’s Corporate Net-Zero Standard Version 1.3.1 remains available for target setting until 31 January 2028, with Version 2.0 validation opening from Q1 2027 4. The SBTi’s supplier engagement guidance is a useful reference for designing the next phase 3.

The choice is to scale, redesign or stop. A pilot that shows the data request was too heavy, or that category managers lacked time, has still done its job if it leads to a better design.

Common pilot mistakes

• Choosing suppliers by willingness rather than emissions weight, so the pilot proves nothing about the categories that matter.
• Leaving category managers out, which turns the pilot into a sustainability survey.
• Asking for a full corporate inventory from small suppliers when energy bills and production data would do.
• Treating better data as reduced emissions.
• Ending at day 90 without a decision, so momentum fades.

For a broader view of category prioritisation across the region, see our guide to supply chain decarbonisation in Asia. If you are designing a pilot with suppliers in China, Hong Kong, Taiwan or elsewhere in APAC, talk to our team.

Sources

1. GHG Protocol, “Corporate Value Chain (Scope 3) Standard”, 2011. https://ghgprotocol.org/corporate-value-chain-scope-3-standard
2. GHG Protocol, “Scope 3 Calculation Guidance”, 2013. https://ghgprotocol.org/scope-3-calculation-guidance-2
3. Science Based Targets initiative, “New Supplier Engagement Guidance: Unlocking the Power of Supply Chains for Decarbonization”, 19 June 2023. https://sciencebasedtargets.org/blog/new-supplier-engagement-guidance-unlocking-the-power-of-supply-chains-for-decarbonization
4. Science Based Targets initiative, “The Corporate Net-Zero Standard”. https://sciencebasedtargets.org/net-zero
5. WBCSD, “PACT Methodology Version 3”, 2 June 2026. https://www.wbcsd.org/resources/pact-methodology-version-3/
6. European Commission, Taxation and Customs Union, “CBAM definitive regime”. https://taxation-customs.ec.europa.eu/carbon-border-adjustment-mechanism/cbam-definitive-regime_en