Educational note. This article is for education only. It is not investment, tax, accounting, or legal advice, and it is not an offer of advisory services from FG Capital Advisors.
Corresponding Adjustments: What Carbon Credit Buyers Should Ask
Carbon credit buyers who may use units toward nationally determined contributions, CORSIA, or other international mitigation purposes need to ask how corresponding adjustments and host Party authorization affect the claim. Those questions are different from a purely voluntary retirement claim. This article sets out the questions a buyer should ask, and how they differ from an authorization-letter threshold test.
When does a buyer actually need a corresponding adjustment?
A corresponding adjustment becomes relevant when the buyer intends to use an internationally transferred mitigation outcome, including an authorized Article 6.4 unit after first transfer, toward a nationally determined contribution or another international mitigation purpose that depends on Article 6.2 accounting. It is not automatically required for every voluntary retirement that a company books as a contribution claim.
That distinction is the one buyers most often blur. A credit can be real, independently verified, and still not be an ITMO. An ITMO can exist, and still be a poor fit if the authorization, first-transfer status, or host reporting is incomplete. The existing article Do voluntary credits need an Article 6 authorization letter? addresses the threshold question of when a letter is needed. This article is the buyer question list that should follow once that threshold is in view. Host-country and mechanism context is also covered in Article 6 carbon market readiness explained.
What should a buyer ask a seller before signing?
The buyer should ask what unit type is being sold, whether the host Party has authorized it and for which uses, whether first transfer has occurred or will occur, and how the host will report the corresponding adjustment. The buyer should also ask what happens if authorization is delayed, changed, or never granted.
| Buyer question | Why it matters | Weak answer |
|---|---|---|
| What unit is this, in official terms? | Voluntary credits, mitigation contribution A6.4ERs, authorized A6.4ERs, and ITMOs are not interchangeable labels | "It is an Article 6 credit" with no unit type |
| Has the host Party authorized this use? | Authorization is what can turn a unit into an ITMO pathway and trigger corresponding adjustment | A draft letter, a verbal assurance, or a letter that authorizes a different use |
| Has first transfer occurred, or when will it occur? | Authorized A6.4 units become ITMOs after first transfer, as that term is used in Article 6.2 guidance | Silence, or an assumption that issuance equals first transfer |
| How will the host report the adjustment? | Corresponding adjustments are applied to an emissions balance used to track NDC progress, not to the national inventory itself | "The host will take care of it" with no reporting path |
| What is the fallback if authorization fails? | The buyer may still have a voluntary credit, which may not support the original international-use claim | No fallback, or a refund clause that ignores claim timing |
Contract mechanics for offtake already have live pages, including what are ERPAs in carbon finance and seven risks buyers price into carbon forward deals. This article does not repeat those clause catalogs. It adds the authorization and adjustment questions that now belong in the same diligence pack.
How do CORSIA and voluntary claims change the questions?
A CORSIA use case should be tested against the current ICAO Eligible Emissions Units document, including vintage limits, and against any authorization conditions the compliance process requires. A purely voluntary retirement claim may not need an ITMO at all. The buyer should state the claim first, then ask only the questions that claim requires.
CORSIA advisory already has a live page at CORSIA advisory. Broader credit procurement remains on high-integrity carbon credit procurement, how to build a carbon credit procurement strategy, and carbon credit buyer due diligence. Integrity-label questions, which are also not a substitute for authorization, remain on ICVCM Core Carbon Principles explained.
What should not be treated as proof of a corresponding adjustment?
A marketing statement, draft letter, registry screenshot without an authorization tag, or seller warranty with no host-Party process behind it, is not proof that a corresponding adjustment will be applied. The buyer needs the official unit type, the authorization decision, and a clear account of first transfer and reporting. If those are missing, treat the credit as a voluntary instrument.
This article is educational. It is not legal, accounting or compliance advice, and it does not determine whether any particular credit is an ITMO. Official UNFCCC Article 6.2 and Article 6.4 texts, plus the host Party's published process, are the controlling sources.
Frequently asked questions
Do all voluntary carbon credit purchases need a corresponding adjustment?
No. Corresponding adjustments apply to internationally transferred mitigation outcomes under Article 6.2 guidance, including authorized Article 6.4 units after first transfer. A company that is only retiring a voluntary credit for a voluntary claim may not be transacting an ITMO at all. The intended use, not the marketing label, decides which questions apply.
Is a letter of authorization the same thing as a corresponding adjustment?
No. A letter of authorization is a host Party decision about authorized use of a mitigation outcome. A corresponding adjustment is the accounting step participating Parties apply when tracking NDC progress after an ITMO transfer. One can exist on a path to the other. Neither is proven by a seller slide that uses the terms interchangeably.
Does issuance of an Article 6.4 unit automatically create an ITMO?
No. Mitigation contribution units have not been authorized and are intended to count toward the host Party's NDC. Authorized units become ITMOs after first transfer, as that term is used in the Article 6.2 guidance. Buyers should ask for the official unit type and transfer status, not assume that 'Article 6' means ITMO.
What is a sensible fallback if host authorization never arrives?
The contract should say whether the buyer will accept a voluntary credit, wait, cancel, or re-price, and how any prepaid value is treated. If the original claim required an ITMO, a later voluntary retirement will not automatically rescue that claim. Silence on the fallback is one of the more expensive omissions in a forward purchase.
Should CORSIA buyers use the same questions as voluntary buyers?
They should start with the intended claim. CORSIA buyers also need the current ICAO Eligible Emissions Units document, including vintage limits, and any authorization conditions their compliance process requires. Voluntary buyers may need none of that, or only part of it. Collecting every document without tying it to a claim is not diligence.
Where should buyers start if they only need the authorization threshold test?
Start with the existing article on whether voluntary credits need an Article 6 authorization letter, and with the Article 6 carbon market readiness page. Use this article when the threshold is already in view and the buyer needs a question list on unit type, first transfer, reporting and fallback. The two articles are companions, not substitutes.
