Glossary›Emissions accounting and measurement›Double counting
Glossary term
Cluster D · D30
Tier 1 · differentiator
Double counting
Definition
Double counting occurs when the same tonne of emissions is recorded more than once. Within a single organisation’s inventory it is an error and must be eliminated. Between different organisations reporting their own value chains it is expected and correct: one company’s Scope 1 emission is another company’s Scope 3, and both report it.
GHG Protocol Corporate Value Chain (Scope 3) Standard (2011)
· chapter 8 ·
In force
On this page
In practice
Two different things share one name, and conflating them produces the wrong fix.
Where
What it is
What to do
Within your inventory
A defect. It happens when a site appears in two source feeds, when a subsidiary reports its own fuel and the parent also captures it through a group fuel card account, when landlord-recovered electricity is picked up from both the outgoings invoice and a sub-meter, and when the same freight movement arrives from both the carrier statement and the supplier’s shipping data.
Eliminate it. Every one of those inflates the total.
Across organisations
The design. The GHG Protocol is explicit that two or more companies accounting for the same emission within Scope 3 is inherent to Scope 3 accounting, and acceptable for reporting, for driving value chain reductions and for tracking targets.
Leave it. Your diesel supplier reports the refining emissions as their Scope 1; you report the same physical carbon as your Scope 3 Category 3; your customer reports it again in their Category 1. Nothing is wrong.
Each party in the chain has some influence over the emission, and the structure exists so that several parties can act on it at once.
Where the Scope 3 categories themselves risk overlap, the standard’s minimum boundaries do the work. Table 5.4 of the Scope 3 Standard sets a minimum boundary per category, which is what stops the same purchased good being counted in both Category 1 and Category 4.
The confusion costs money when a controller tries to eliminate the second kind. Netting your Scope 3 down because your supplier already reported those emissions produces an understated, non-compliant figure.
What the assurer does with it
The assurer tests intra-inventory double counting directly, because it is a completeness and accuracy assertion with a testable population. They cross-check the site listing against the meter listing, the entity listing against the fuel account listing, and any source that appears in more than one feed. The standard procedure is an overlap analysis: sort the inventory by site and by account and look for the same physical asset arriving twice under different names.
They accept a documented de-duplication step with a stated rule (for example, that group fuel card volumes are excluded from subsidiary returns) applied consistently and evidenced. They reject a total that exceeds an independent control total such as general ledger fuel expense divided by average price, a site appearing under two naming conventions with no reconciliation, and any elimination applied as a single top-level adjustment with no supporting schedule.
Across organisations they test nothing, because there is nothing to test. Where an entity has reduced its Scope 3 to avoid overlap with a supplier’s reporting, the assurer treats that as an understatement and asks for the gross figure.
Commonly confused with
Double counting of carbon credits, which is a different problem entirely: two parties claiming the same abatement against their own targets. That is a credit integrity issue governed by the crediting scheme’s registry and cancellation rules, not an inventory accounting issue.
Sources
1
Corporate Value Chain (Scope 3) Accounting and Reporting Standard, full text
GHG Protocol
2
3
Corporate Value Chain (Scope 3) Accounting and Reporting Standard (2011)
GHG Protocol
Review status
Review required
Last reviewed
15 September 2026
Editorial pass, unsigned
Reviewer required
Carbon accounting specialist
Next scheduled review
1 July 2027
Part of
Cluster D, Emissions accounting and measurement
49 terms from the head term carbon accounting down to individual Scope 3 categories and the mechanics of factors, boundaries and data quality. The largest cluster in the glossary.
Related terms
Where the minimum boundary table that prevents category overlap lives
The split that decides which side of the value chain an activity sits on
The boundary error that most often produces intra-inventory duplication
Related questions
How do we work out which Scope 3 categories are material for us?
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You screen all fifteen GHG Protocol categories, estimate each roughly off accounts payable spend, and document why you included or excluded each one. The screen is the deliverable as much as the answer, because the practitioner will test the reasoning behind an exclusion at least as hard as the numbers behind an inclusion. Expect the answer to be concentrated in a handful of categories.
Do we have to report Scope 3 in year one?
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No. AASB S2 gives first-time reporters relief from disclosing Scope 3 greenhouse gas emissions in their first annual reporting period, and Scope 3 is required from the second year. Taking the relief in year one is normal, but the supplier data work needs to start in year one anyway.
What evidence do we need for each emissions number?
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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.
Where this sits commercially
Carbonhalo eliminates duplication inside the inventory and leaves the inter-company overlap where the standard puts it, which is the opposite of what most first drafts do.
Other terms in this cluster
Double counting