What evidence do we need for each emissions number?

Every reported number needs a source document you did not create for the report, the activity data drawn from it, the emission factor and its published edition, and the calculation joining them. Fleet fuel needs litres from fuel card statements, electricity needs kWh by site from retailer invoices with the matching state factor, and refrigerants need kilograms by gas type from service records.

What will our auditor actually ask for?

In year one they ask for evidence behind the disclosures that are actually assured: Scope 1 and Scope 2 emissions, your governance disclosures, and the specified strategy paragraphs on climate risks and opportunities. In practice that means source documents, a calculation they can rebuild from those documents, and minutes showing the governance you described actually happened.

Can we use spreadsheets, or will the auditor reject them?

Spreadsheets are acceptable and no Australian standard requires software. What gets rejected is an unauditable spreadsheet: hard-coded numbers with no source, broken formula chains, no version control and no record of who changed what. A disciplined spreadsheet passes assurance and an undisciplined system does not.

Glossary›Assurance, audit evidence and working papers›Audit evidence

Glossary term

Cluster A · A2

Tier 1 · differentiator

Audit evidence

Definition

Audit evidence is the information an assurance provider uses to decide whether a climate disclosure is materially correct. It includes invoices, meter readings, contracts, system reports, calculation files, written management responses and the assurer’s own recalculations. Evidence must be both sufficient in quantity and appropriate in quality before a conclusion can be signed.

ASSA 5000

· evidence requirements · in force for reporting periods beginning on or after 1 January 2025

On this page

In practice
What the assurer does with it
Commonly confused with
Sources
Related terms
Related questions

Cluster

A · Assurance, audit evidence and working papers, 47 terms

In practice

Evidence has a hierarchy and most first-time reporters do not know it. Strongest is a document created by an independent outside party at the time of the activity: an electricity retailer’s invoice, a fuel card statement, a signed lease. Next is an internal record generated by a system with controls over it, such as a fleet management report. Weakest is a document prepared by management for the purpose of the assurance engagement, and weaker again is an oral answer to a question.

That ranking has a direct cost consequence. If your Scope 1 fuel figure rests on a spreadsheet a site manager types into monthly, the assurer needs far more testing to reach the same conclusion than if the figure comes off a fuel card statement.

What the assurer does with it

An assurer accepts evidence that is external in origin, contemporaneous with the activity, complete for the period, and directly relevant to the assertion being tested. They reject evidence recreated after the fact, evidence covering a different period, evidence from a system nobody can explain, and evidence that supports a different figure to the one reported. Where evidence is weak they do not simply fail the number; they extend testing, seek corroboration from a second independent source, or record a scope limitation. Expect them to approach the same figure from two directions: once from the report back to source, and once from an independent population total forward to the report.

Commonly confused with

Evidence in a financial statement audit. The concept is identical; the subject matter is not. There is no emissions general ledger, no trial balance and no double entry, so completeness cannot be proved by agreeing to a control account. Assurers compensate by reconciling to the financial ledger wherever a monetary equivalent exists.