ESG evidence for suppliers
ESG evidence for suppliers: what documents actually support your answers?
A practical guide to matching ESG statements with sources, documents, scope and reporting periods.
Quick answer
Start with the request, not the spreadsheet.
Supporting evidence is not just any document that mentions sustainability. It needs to support the specific answer being made.
The core check is simple: what is the statement, what is the source, what document or calculation supports it, and does that evidence match the company, site, period and claim?
Match the claim.
A certificate, policy or report must support the exact statement, not just the general topic.
Check scope.
Evidence for one site, facility or legal entity may not support a group-wide answer.
Check period.
Current documents and historical reporting periods should not be mixed without explanation.
Check approval.
A draft policy, template or working file is not the same as an approved company document.
Start with the statement, not the document folder.
Evidence should be selected after you understand the answer it needs to support. A broad sustainability brochure may be useful background, but it is weak evidence for a specific KPI, policy status or site-level claim.
For each answer, ask what exactly is being claimed, where the information came from and what document, calculation or record supports that claim.
Evidence logic
Answer - source - supporting evidence - scope - period - review.
Different document types support different claims.
Supplier ESG evidence can include policies, certificates, procedures, audit reports, invoices, KPI reports, calculations, training records and internal approvals. These documents are not interchangeable.
A certificate may show that a management system is certified for a defined scope. An invoice may support activity data. A calculation file may support CO2e. A policy may show a formal commitment, not every operational action.
Policies
Can support formal commitments if approved, current and applicable to the right entity or scope.
Certificates
Can support a certified management system within the certificate's stated scope and validity period.
Calculations
Can support KPIs when activity data, method, factors, assumptions and result remain traceable.
Operational records
Can support implementation where the record actually documents the process, training, audit or control.
A policy is not evidence of everything under that topic.
Policies are often requested, and they can be important. But a policy does not automatically prove implementation, performance, training or historical practice.
If a policy is missing, the company may create one to reflect its current decisions and responsibilities. That new document should be treated as current evidence after proper approval, not as proof that the policy existed earlier.
Policy is not implementation. Implementation is not evidence unless there is a source that shows it.
Emissions evidence needs a calculation trail.
For greenhouse gas answers, a final CO2e number is only part of the evidence. The supporting file should show the boundary, activity data, source documents, emission factors, method and assumptions.
This is especially important when the questionnaire asks for Scope 1, Scope 2, renewable electricity, market-based or location-based calculations, or site-specific emissions.
- Boundary: entity, site, facility or group
- Activity data: kWh, litres, tonnes, kilometres or other inputs
- Source: invoice, meter, fuel card, supplier statement or system extract
- Emission factor: source and year
- Calculation: how the CO2e result was produced
- Review: who checked the figure and assumptions
Some documents look useful but do not support the answer.
Weak evidence is not always false. It is often just too broad, too old, not approved, not connected to the right scope or not specific enough for the answer.
The safest approach is to state what the document actually supports and not stretch it beyond that.
- General marketing brochures
- Unapproved policy templates
- Old certificates outside their validity period
- Group documents used for a site without confirming coverage
- Screenshots with no source, date or scope
- Documents created after the period they are supposed to evidence
Do not use a document to say more than the document can support.
Keep an evidence register for reuse.
A simple evidence register makes future customer requests easier. It records which document supports which statement, the applicable scope, owner, validity and any limitation.
Reuse the underlying information, not the answer blindly. A new customer may ask for a different period, site, platform format or evidence type.
- Evidence name
- Supported statement
- Legal entity, site or group scope
- Reporting period or validity
- Internal owner
- Approval status
- Known limitations
Evidence review
Need to know which documents support your answers?
Send the customer request and available documents. We can map each statement to its source, identify evidence gaps and prepare a response package for internal confirmation.
FAQ
Frequently asked questions
What counts as ESG evidence?
It depends on the answer. Evidence may include policies, certificates, invoices, calculations, procedures, training records, audit reports or other documents if they support the specific statement, scope and period.
Is a policy enough evidence?
A policy can support a formal commitment if it is approved and applicable. It does not automatically prove implementation, performance or historical practice.
Can a new document close a gap?
Yes, a company can close a current gap by creating and approving a real document or process. It should not be presented as historical evidence unless it actually existed in that period.