How to Buy Carbon Credits: A Guide for UK Businesses

In Short: Businesses can buy carbon credits directly from projects, through specialist providers or brokers like C Level, or on marketplaces. Before buying, define what the credits are for, choose the carbon outcome, check the project, methodology and registry evidence, and agree how the units will be retired.

A carbon credit, for all the talk of rainforests and peat bogs that attends its sale, is a simple line of text in a database. Each issued credit carries a serial number and can be traced to a project, a methodology and a “vintage”: the year, or period, in which the tonne of carbon dioxide equivalent it represents is deemed to have been kept out of the atmosphere or taken out of it.

These carbon databases are called ‘registries’.

Verra runs the registry for its Verified Carbon Standard; Gold Standard keeps its own Impact Registry; and Plan Vivo records credits issued under its community-focused standard. Plan Vivo is the standard we use most often at C Level because its model puts local communities and landholders at the centre of projects, rather than treating carbon as the only outcome.

For the most part, a carbon credit buyer takes delivery of nothing save registry proof. When a company uses a credit, the registry changes its status to “retired”, so that it can never be sold or used again, and the public record then shows which units were retired, when, and often on whose behalf. Like wine, credits are sold by vintage. Unlike wine, they tend to lose value as they age. In 2025, the analysts at MSCI found that credits from after 2019 commanded a premium over older vintages, and the gap was widest against lower-rated rainforest-protection credits from 2012 to 2018.

All of this is central to our work here at C Level because, as with wine, there is an enormous variety in what you buy. Having visited these projects ourselves and, in some cases having been intimately connected with their development, our team’s experience means that credits we sell have been rigorously assessed.

What lies behind that line of text which represents one individual carbon credit varies tremendously. It might be a cookstove in northern Ghana that burns less wood than the open fire it replaced, a drained peatland in the Flow Country of Caithness that has been wetted again, or biochar worked into an English field. It might be carbon dioxide drawn from the air by a plant in Iceland and pumped into basalt, where it slowly turns to stone. On a broker’s spreadsheet these can sit in neighbouring rows, priced in the same unit. Some conventional credits have changed hands for less than a dollar a tonne. Some engineered removals have cost more than a thousand.

There are two reasons for the gulf. The first is that the activities differ in how certain, how lasting and how expensive their carbon benefit is. Carbon mineralised in Icelandic rock will stay there on geological timescales; carbon held in a forest is exposed to fire, disease and the next owner’s plans for the land. The second is time. Some credits have already been monitored, independently verified and issued, and can be retired the afternoon they are bought. Others are promises.

A company that begins by comparing prices, therefore, is mostly comparing unlike things. Good project sourcing always begins with a deep series of conversations around what the purchase is meant to achieve; whether they need credits that exist now, or are prepared to pay for tonnes that will arrive in the 2030s; what kind of carbon outcome they want; and what they intend to say about it afterwards, a question British advertising regulators have lately made harder to fudge. Until those questions are answered, I would treat a price comparison as largely meaningless. Once they are, most of the spreadsheet falls away.

If you’d like to begin that conversation, please get in touch to take the first step.

How to buy carbon credits in seven steps

For a business, buying carbon credits is less like shopping than like commissioning a building. The brief comes first, and the order of what follows matters.

Here’s our recommended process:

1. Decide what the purchase is for. The company may need issued credits it can retire now, may want to finance climate action that will pay off later, or may want both.
2. Set the quantity or the budget. Where the purchase is tied to emissions, start from the relevant footprint. Where it is not, set a separate climate-finance budget.
3. Choose the carbon outcome. Removals, reductions and avoided emissions are different things, and so are carbon stored for a decade and carbon stored for a millennium.
4. Choose where to buy. Directly from a project, through a specialist provider or broker, on a marketplace, or through a forward or offtake agreement. There are pros and cons to each.
5. Examine the specific carbon project and units. Programme, methodology, vintage, issuance status, registry, volume and the evidence behind them.
6. Agree price, delivery and retirement. For future credits, agree in writing what happens if the tonnes arrive late, or not at all.
7. Verify the retirement and the claim. Keep the registry record, and make sure nothing the company says goes further than the purchase and the evidence allow.

Much of what follows is an attempt to stop those seven decisions from collapsing into a single question about price.

What should a company decide before buying carbon credits?

Any conversation with C Level begins with a fact-finding around what the credits are for, how far along the road to delivery they must be, and what the company will eventually need to prove.

A business that must retire credits against this year’s report should begin with issued units. A proposal for removals expected in 2035 may be an admirable piece of climate finance, but it does not solve that problem. A business whose aim is to put money into restoration before the carbon has been delivered faces the opposite case. If it insists on issued units, it is arriving after the difficult and uncertain work has already been paid for by somebody else.

Nature projects sharpen the point, because nature keeps its own schedule. Saplings have to be planted and then have to survive. The drainage ditches cut into a peat bog in the nineteen-seventies have to be blocked, and the water table allowed to rise. Farmers and landholders have to be recruited, persuaded and paid. Someone has to come back, year after year, and measure what happened. The tidiness of the final unit, one tonne, can conceal a decade between the first pound of finance and the credit on the registry.

Your company should also decide whether it prefers to pay for carbon removed from the atmosphere or for emissions reduced or avoided. I increasingly favour regeneration and removals in our own work, but I would not use the label as a verdict on quality. Faced with a badly evidenced removal and a well-run avoided-emissions project, I would choose the latter.

Finally, the company should decide roughly how the purchase will be described. Funding climate action beyond one’s own value chain is a different statement from claiming to have neutralised residual emissions in a net-zero plan (something we would never stand behind). The wording need not be final when procurement starts, but its meaning should be clear enough that the company does not buy one thing and then ask its communications team to make it sound like another.

Some of those choices are preferences. Others are filters. If the board has approved removals only, if the company needs issued units that can be retired this year, or if procurement requires a named programme or registry route, those conditions should be written down before the market is approached.

It is also worth recording where each condition comes from. A legal requirement, a target framework, an internal purchasing policy and C Level’s own recommendation are not the same kind of rule. Buyers get into trouble when a preference is treated as mandatory, or when a genuine requirement disappears into a generic “high-integrity” checklist.

Once the non-negotiables are fixed, the first shortlist becomes much easier. Most of the market can be ignored.

How many carbon credits should a business buy?

Where a purchase is linked to a company’s emissions, the quantity should follow from its footprint and its climate policy, not from a supplier’s price list.

There is a surprisingly easy way to set a carbon commitment, which is to do the arithmetic backwards. The company has a hundred thousand pounds. A project is offered at twenty pounds a tonne. The commitment becomes five thousand tonnes. Nothing is wrong with the sum. The trouble is that the market price and the size of the budget have quietly decided the scale of the company’s response to climate change.

The opposite shortcut is not much better. A footprint of ten thousand tonnes does not, by itself, oblige a company to buy ten thousand credits. It may choose to fund climate action in proportion to the emissions it cannot yet cut; it may set a separate budget; it may split its money between issued credits and early-stage projects; or it may be working within a framework that gives the purchase a narrower purpose. The footprint tells a company how much it emits. It does not write the procurement policy.

For businesses without a credible emissions baseline, that work usually comes first. C Level’s Business Carbon Footprint Calculator and carbon footprint consultancy are designed for that earlier stage.

Where can businesses buy carbon credits?

Businesses can buy carbon credits directly from project developers, through specialist providers and brokers, on marketplaces, or through forward and offtake agreements for credits that will be issued in future.

At the moment of payment, the routes look much alike. They differ in how much of the work they leave with the buyer.

Buying route	What the buyer is really choosing
Project developer	A direct relationship with the organisation producing the credits, with more of the diligence and paperwork left to the buyer
Specialist carbon provider	Sourcing, evidence review, procurement and retirement handled as part of the purchase
Broker	Access to a wider range of supply, often useful for larger volumes, with a need to understand pricing, fees and counterparties
Marketplace	Quick access to listed inventory and visible prices, with more responsibility on the buyer to judge what is suitable
Forward purchase or offtake	Future supply from a project or portfolio, usually with more delivery risk and a longer contract

A large and experienced buyer can go direct and do the diligence in-house. For a company that buys once a year, cutting out the intermediary can be a false economy, if its sustainability team then has to establish the status of the units, read the methodology, negotiate the terms of future delivery, arrange retirement and assemble the evidence on its own.

The seller and the credit also need to be judged separately. A reputable provider may be excellent at sourcing, contracting and retirement without every project on its books being right for every buyer. The reverse holds, too: a compelling project says nothing about whether the organisation selling its credits keeps proper records. The first question is, Can we safely do business with these people? The second is, Do we want these particular tonnes?

Should you buy from one carbon project or a portfolio?

A named project gives the buyer more connection and project-specific evidence, while a portfolio can spread delivery, geography, methodology and operator risk across several sources.

Neither route is automatically stronger. A named project is often easier to understand and communicate. The company can see where the work is happening, follow the project documents and, in some cases, build a relationship with the organisation delivering it. For buyers that care about a particular geography, community or restoration programme, that specificity may be part of the reason for buying.

It also concentrates risk. If the project’s verification is delayed, its methodology changes, local implementation falters or future issuance is lower than expected, more of the buyer’s programme is exposed to the same problem.

	Named project	Portfolio
Connection	A close link to one project and its people	A broader supply base
Communication	Easier to explain one project and its evidence	Harder to tell as one story
Delivery risk	Concentrated in one project	Can be spread across projects, operators and geographies
Visibility	Clear project-level documents	May show less about each project
Suits	Strategic or place-based funding	Buyers who put resilience and volume first

A portfolio gives up some of that singular identity in exchange for diversification. The question to ask of a portfolio is whether its underlying risks are genuinely different: different operators, geographies, methodologies, delivery stages or sovereign exposures. Five forestry projects in the same jurisdiction may look varied on a presentation slide while remaining exposed to many of the same risks. Do not count projects. Compare the risks that actually differ.

For a buyer that needs dependable current-year retirement, diversification may be valuable. For a company deliberately building a long-term relationship with a particular restoration project, concentration may be entirely intentional. Our page on carbon credits for business explains how we build a shortlist for either.

What information should you ask for before buying carbon credits?

Before approving a purchase, a buyer should be able to identify the exact carbon product, not a category such as “premium forestry credits” or “verified removals”.

For an issued credit, that means enough detail for a stranger to find the tonnes on a public registry, and enough to know whether the company can use them as it intends.

Carbon credit information	What you should establish
Project	The project’s name and its registry ID
Crediting programme	The rulebook the project is certified under
Methodology	The methodology and its version
Location and type	The country and the project type
Carbon outcome	Removal, reduction or avoided emission
Vintage	The year or period the tonnes relate to
Issuance status	Whether the units have been issued, or are still expected
Quantity	How many units are available
Registry and serial numbers	Which registry holds the units, and their serial numbers where possible
Price and fees	The price per tonne and any material fees
Retirement	How, and in whose name, the units will be retired
Ownership and custody	Who holds the units between purchase and retirement
Transferability	Whether the units can be transferred as required
Restrictions on use	Any limits on sale, transfer, retirement or intended use
Beneficiary name	Whether the registry can record the buyer or intended beneficiary correctly

If a supplier cannot tell you exactly what the unit is, the buyer does not yet have a complete offer.

For a material purchase, the last four rows deserve more than a tick. Who owns the units between purchase and retirement? Whose registry account holds them? Can they be transferred, or will the provider retire them directly? If the company needs a particular retirement record or beneficiary name, can the registry and the transaction structure actually produce it? These questions sound administrative until one of them prevents the buyer doing what the purchase was meant to support.

Future delivery adds another layer. The agreement should state when the credits are expected, which milestones remain, how much of the volume is firm and how much merely indicative, whether the seller may substitute other credits, and what happens if fewer units are issued than forecast.

None of this is administrative decoration. It is a description of the thing being bought. The crediting programme is the rulebook. The methodology is the arithmetic by which the carbon is counted. The project documents show how the rules have been applied on a particular hillside or in a particular village. Verification is an independent assessor checking the sums. The registry records what actually exists. By the time a purchase reaches procurement, these pieces should fit together without gaps.

How can you tell whether a carbon credit is high quality?

A recognised standard is a useful starting point, but the judgement about quality still has to be made project by project, and unit by unit.

Verra, Gold Standard, Plan Vivo and the UK’s Woodland and Peatland Codes work in different ways, but each sets rules under which projects are designed and their carbon outcomes assessed. The name of the programme tells a buyer which rules apply. It does not mean that every credit issued under those rules is equally additional, equally durable or equally suitable. In 2023, an investigation by the Guardian, Die Zeit and SourceMaterial concluded that most of the rainforest-protection credits it examined under Verra’s standard were unlikely to represent genuine reductions. Verra disputed the findings, and has since revised its methodologies, but the episode taught many buyers that a respectable logo is where diligence begins, not where it ends.

1. Programme
2. Methodology
3. Project
4. Monitoring
5. Verification
6. Issuance
7. Unit

When I assess an issued credit, I give the registry record and current project documents more weight than the sales page. The registry should lead back to the project and its paperwork: depending on the programme, the project design document, the methodology, monitoring reports, validation and verification reports, and the history of issuance. The sales page explains the proposition; those records show what has actually been delivered.

Beneath most of this lies additionality. The buyer is not simply paying for a good deed; the case for the credit depends on the carbon outcome being additional to what would otherwise have happened, measured against a baseline the methodology defines. A forest that was never going to be felled cannot be saved, however handsomely one pays for its preservation.

Stored carbon raises the question of what might release it, and who is responsible if that happens: in a forest, fire, disease, or a change in how the land is used. Leakage matters where stopping an activity inside a project’s boundary merely moves it next door. Double counting matters because a tonne only works as a tradable unit if the same outcome is not sold, or claimed, twice.

Claims about communities deserve the same scrutiny. If a project calls itself community-led, I want to know more than what percentage of revenue stays local: who controls the land, who takes part in decisions, who is paid and on what terms, how complaints are heard, and who bears the cost if the project falls short. A good project does not have to be free of risk. It does have to make its risks visible enough for a buyer to decide whether to accept them. Our guide to high integrity carbon credits sets out these checks in more detail.

How much do carbon credits cost?

There is no single useful price for a carbon credit, because credits that each represent a tonne of carbon dioxide equivalent are not economically interchangeable.

MSCI’s data for 2025 shows how wide the range is. Conventional credits traded from under a dollar to nearly fifty dollars a tonne, while some engineered removals exceeded a thousand. Project type, quality rating, region and vintage were the main drivers of price, and newer vintages carried a significant premium.

A corporate buyer should not read that spread as a menu running from cheap to dear. It is evidence that the market is pricing very different activities, and very different risks, through the same unit of account. An issued credit and a future credit may both cost ten pounds and still be quite different bargains: one can be retired tomorrow, while the other depends on years of planting, monitoring and verification. Two issued credits can differ just as sharply, because one methodology is in greater demand, one project’s supply is scarcer, or one outcome is expected to last far longer.

That is why I would compare the specification before the price. Once a buyer has filtered for the outcome, status, quality, timing and evidence it actually wants, price becomes a far more useful way of choosing between what remains. Before comparing two prices, check that they share:

• the same project type;
• the same delivery status, issued or future;
• the same market stage;
• the same vintage;
• a similar volume;
• the same programme and methodology;
• the same kind of price, an executed trade rather than an asking price;
• the same treatment of fees and taxes.

C Level’s separate carbon credit price guide looks at pricing in more detail.

Should a business buy issued carbon credits or future credits?

A business should buy issued credits when it needs units that already exist and can be retired, and future credits when it is deliberately accepting delivery risk in return for earlier access to supply, or in order to fund a project when funding matters most.

	Issued credit	Future delivery
The unit	Already exists	Expected later
Delivery risk	Much of it already resolved	More project and delivery risk remains
Retirement	Can usually be retired straight away	Cannot be used as an issued unit before delivery
Price	Often a higher price per tonne	May be cheaper, and funds the project earlier
Best for	A current retirement need	A buyer deliberately accepting future delivery

Earlier finance can be more useful to the project. It also transfers more uncertainty to the buyer.

Neither choice is inherently more virtuous. There is something appealing about paying for a project before its outcome is known. In nature restoration, waiting for an issued tonne can mean arriving years after the tree nursery was built, the seedlings planted, the landholder persuaded and the early losses absorbed. Early money is useful precisely because it arrives before anyone can be sure of the result.

The uncertainty, though, is real. The Woodland Carbon Code describes a Pending Issuance Unit as a promise to deliver a verified unit in future, and says plainly that delivery is not guaranteed. A buyer can hold the promise, but cannot retire it as a verified Woodland Carbon Unit until the carbon has been measured and confirmed.

The same principle applies to forward purchases generally. Before signing, a buyer should know how far the project has actually travelled: whether it exists only on paper, whether it has been validated, whether its finance is secured, whether work on the ground has started, whether the forecast volume rests on measurement or on modelling, and whether the credits are tied to that project or can be swapped for something else. The phrase “forward carbon credit” covers a surprisingly wide range of commitments. The contract should make clear which one is being entered into.

What should a carbon-credit contract cover?

A carbon-credit contract should describe the units, or the future delivery, clearly enough that price, timing, retirement and failure can all be dealt with without reference to the sales presentation.

For a straightforward purchase of existing credits, the essentials are familiar: the project, the type of unit, the vintage, the quantity, the price and fees, the registry, the instructions for transfer or retirement, and the evidence to be supplied afterwards.

Future delivery is where the contract earns its keep. A press release announcing that a company has agreed to buy a hundred thousand tonnes does not say whether those tonnes are guaranteed or merely a ceiling over ten years, when the money changes hands, whether the project’s own finance is in place, or what the buyer receives if the credits never materialise. A procurement team should therefore read closely the delivery schedule, the firm volume, the timing of payments, any conditions precedent, the rights of substitution, and the remedies for shortfall. If a particular project is the reason for buying, unrestricted substitution may defeat the purpose. If the buyer mainly wants dependable supply, some flexibility may be welcome.

A long-term purchase commitment can make a project easier to finance, because it gives future revenue more certainty. It does not, by itself, prove that the remaining development capital, working capital or delivery dependencies have been solved.

The contract is where an attractive story about a project becomes an allocation of risk.

What happens after you buy carbon credits?

For issued credits bought for use, the transaction is not complete when the supplier is paid. It is complete when the credits are retired on the relevant registry.

1. Project
2. Verification
3. Issuance
4. Purchase or transfer
5. Retirement
6. Registry record

Gold Standard describes its Impact Registry as the source of truth for the issuance, holding, transfer and retirement of its units, each of which carries a unique serial number that allows it to be traced through its life. Verra’s registry records the same stages and publishes issuance and retirement records. The UK Land Carbon Registry records the status and serial numbers of Woodland Carbon Code units.

The route to retirement varies. A large buyer may hold units in its own registry account and retire them itself; a specialist provider may buy and retire them on the company’s behalf. Either works, provided the record is clear. The test is whether somebody who had nothing to do with the original purchase could reconstruct it: the project, the quantity, the serial numbers, the date of retirement and the registry entry. A certificate is a pleasant summary. It should not be the only place the transaction can be found.

What can a business say after buying carbon credits?

The safest claim is one that describes the transaction accurately: what was funded, what carbon outcome the credits represent, whether they were issued and retired, and which project they came from.

Retiring a voluntary carbon credit does not make the original emission vanish from a company’s Scope 1, 2 or 3 inventory. The purchase sits alongside the work of cutting those emissions, not in place of it.

Claims become harder to defend when the language moves from describing climate finance to making larger assertions about a company or a product. In 2023, the Advertising Standards Authority and the Committee of Advertising Practice advised marketers to avoid unqualified claims such as “carbon neutral” and “net zero”, to explain the basis of any such claim, to distinguish offsetting from reductions in emissions, and to give information about the offsetting scheme used. For a sustainability team, that is one more reason to think about the message before making the purchase.

If a company intends to say that it funded five thousand tonnes of verified removals from a named project and retired the credits, the procurement process can be designed to produce evidence for exactly that sentence. If it wants language that implies something about a product’s total climate impact, or its progress towards net zero, that claim has to be tested against the relevant reporting and advertising rules, rather than inferred from the fact that credits were bought.

The stronger claim is not always the better one. I would rather see a company say exactly what it funded than reach for a grander label that has to be explained afterwards. A precise account of what the company paid for is often easier for an auditor, a customer or an employee to understand.

What carbon-credit evidence should a company keep?

A company should keep enough evidence to reconstruct both the transaction and the reasoning behind it: the contract and invoice, the specification of the project and units, the registry and retirement records, the project and verification documents it relied on, and the approved wording used in reports or marketing.

For a significant purchase, I would keep a one-page decision record alongside the registry and project documents. It should say why these units were chosen, what alternatives were considered, the main risk the company knowingly accepted, any limitation in the evidence, and what would cause the decision not to be repeated.

That is different from the audit trail. The registry proves what happened to the credit. The decision record preserves why the company thought buying it was sensible.

That last part is easily overlooked, because carbon credits are often treated as finished products. The evidence beneath them is not static. Methodologies are revised. Projects are verified again. New monitoring data arrives. Guidance on claims changes. A company may want to talk about a project three years after the people who bought the credits have moved on. A decision that was defensible in 2026 should not have to be reconstructed from somebody’s inbox in 2029. At a review, the question is not whether the company still has the certificate. It is whether it would make the same decision on the evidence available now.

How does C Level help businesses buy carbon credits?

C Level helps businesses define what they need, find suitable projects, examine the carbon and project evidence, buy or fund the right units, and keep a clear record of what happened afterwards.

We have worked in corporate carbon and community-led nature projects since 2000, and that has made us wary of treating the tonne as the beginning of the conversation. By the time a unit appears on a registry, there is a project behind it, a methodology, a history of financing and, very often, years of work in the field. Our emphasis now is on community-led regeneration and carbon removal, particularly projects where we understand the work behind the credits rather than simply the inventory for sale.

For a buyer, the process starts with the brief. From there, we can establish which projects fit it, what evidence exists, whether the carbon is already issued or still to come, what it costs and how much is available, how retirement will be handled, and what records the company will receive.

You can see the projects we work with on our carbon projects page.

Sources and methodology

This article was checked against current registry, standards, regulator and market sources on 30 September 2026.

• Verra, Registry overview. Source for Verra as a nonprofit that runs the registry for its standards, and for the issuance and retirement records it publishes. View the registry overview.
• Verra, Verified Carbon Units. Background on the units issued under the Verified Carbon Standard. View Verra’s explanation.
• Gold Standard, Impact Registry. Source for the registry as the record of issuance, holding, transfer and retirement, and for unique serial numbers that trace each unit. View the registry page.
• Woodland Carbon Code, What you can buy. Source for Pending Issuance Units as a promise of a future verified unit that is not guaranteed, verification at year five and at least every ten years, and conversion into Woodland Carbon Units. View the guidance.
• Woodland Carbon Code, Registry rules of use. Source for the unit statuses and serial numbers recorded on the UK Land Carbon Registry. View the rules.
• Woodland Carbon Code, How to buy and use units. Source for the registry holding woodland and peatland units, and for waiting until units are verified and converted before using them. View the guidance.
• The Guardian, Revealed: more than 90% of rainforest carbon offsets by biggest certifier are worthless, 18 January 2023. Source for the investigation with Die Zeit and SourceMaterial, and Verra’s dispute of its findings. View the investigation.
• Advertising Standards Authority and Committee of Advertising Practice, Environmental claims: carbon offsetting and carbon neutral. Source for the February 2023 advice on unqualified “carbon neutral” and “net zero” claims, explaining the basis of a claim, and giving information about the offsetting scheme. View the advice.
• MSCI, Investor-grade tools to aid the global carbon market, June 2025. Source for the price range from under $1 to nearly $50 a tonne, engineered removals above $1,000, the main drivers of price, and the premium for credits from after 2019. View the analysis.
• MSCI, Carbon credits come of age in 2025. Background on the premium paid for higher-quality credits. View the analysis.