What the data reveals about buyer behavior, portfolio risk, and the emerging quality tier in 2025

The voluntary carbon market in 2025 tells two stories. In one, transaction volumes have contracted 25% from their 2023 peak, prices have softened, and headlines about junk credits continue to erode public confidence. In the other, retirement activity has held steady, a quality tier is emerging around the Integrity Council's Core Carbon Principles, and the price premium for high-quality credits has never been higher. Both stories are true. What matters for corporate buyers is which side of the divide their portfolio sits on.

This analysis examines what actually happened in the market this year—who bought what, how quality differentiation is playing out, and what the patterns suggest about the road ahead. ---

I. The Landscape Has Changed

The voluntary carbon market contracted in 2024-2025, but the headline decline in trading volume obscures a more nuanced story. According to Ecosystem Marketplace's State of the Voluntary Carbon Market report, total transaction volume fell 25% in 2024 compared to 2023. Yet credit prices declined only 5.5%, and retirement volumes—the ultimate measure of demand—remained remarkably stable.

The divergence suggests a market in transition, not collapse. What's happening is less a retreat from carbon credits than a flight to quality. Buyers are purchasing fewer credits, but the credits they're buying command higher prices.

The market is bifurcating. Credits that meet emerging quality standards—particularly the ICVCM Core Carbon Principles—trade at premiums. Credits that don't are becoming increasingly difficult to use in corporate claims without reputational risk.

By Q3 2025, 16.63 million credits had been issued with CCP-approved labels, according to Sylvera's Carbon Data Snapshot. This represents a small fraction of total supply, but the direction is clear: a quality tier is forming, and buyers are gravitating toward it.

Key 2025 Market Indicators (VCM.fyi Data)

• 7,255 distinct buyers active in the past 12 months
• 1,616 buyers active in the past 60 days
• 62,783 retirement transactions recorded YTD 2025
• 69,337 retirement transactions in all of 2024
• Transaction pace suggests 2025 will approximately match 2024 volumes

II. What Corporate Buyers Actually Did in 2025

VCM.fyi tracks retirement activity across the major registries—Verra, Gold Standard, American Carbon Registry, Climate Action Reserve, ART TREES, and others. The buyer data reveals patterns that aren't visible from registry-level statistics alone.

The Top 10 Buyers by 12-Month Volume

| Rank | Buyer | 12m Volume | Top Category | Last Purchase | | | 1 | Eni Upstream | 5.9M | Forest | Feb 2025 | | | 2 | Shell | 5.7M | Forest | Dec 2025 | | | 3 | TASC SA | 3.6M | Fuel-switching | Jun 2025 | | | 4 | Yamato Transport | 2.1M | Renewable energy | Aug 2025 | | | 5 | Eni Plenitude | 1.3M | Forest | Feb 2025 | | | 6 | PetroChina Int'l | 1.1M | Forest | Dec 2025 | | | 7 | VistaJet | 0.8M | Renewable energy | Nov 2025 | | | 8 | 4AIR | 0.7M | Renewable energy | Aug 2025 | | | 9 | Bayer AG | 0.7M | Forest | Dec 2025 | | | 10 | ZIPAIR Tokyo | 0.7M | Renewable energy | Sep 2025 | |

The list is dominated by two sectors: oil & gas and aviation. Both face distinct pressures—oil majors are managing scope 3 emissions claims while navigating court challenges to their climate strategies, while aviation is preparing for CORSIA compliance. The Japanese logistics and aviation sectors (Yamato, ZIPAIR) are notably active, reflecting Japan's corporate carbon neutrality commitments.

Category Composition: The Forest Paradox

Forest credits remain the dominant category among large buyers, despite years of negative press about REDD+ projects. Shell's 2025 portfolio is 77% forest credits. Eni's is 100% forest. This creates an apparent paradox: the credit type with the most reputational baggage is still the credit type major buyers are acquiring in bulk.

The explanation lies in availability and price. High-quality removal credits—biochar, enhanced weathering, direct air capture—remain scarce and expensive. The 78 biochar projects in the database have issued far fewer credits than the 1,923 forest projects. Buyers with large volume needs can't source enough removal credits at prices their procurement budgets can absorb. ---

III. The Quality Tier Takes Shape

The Integrity Council for the Voluntary Carbon Market (ICVCM) spent years developing the Core Carbon Principles—a benchmark framework for credit quality. In 2025, that framework became operational. The question is: how much of the market actually meets it? | Quality Marker | Projects | % of Total (11,093) | | | ICVCM CCP-labeled | 192 | 1.7% | | | CORSIA-eligible | 224 | 2.0% | | | Article 6 authorized | 33 | 0.3% | | | CCB certified | ~800* | 7.2%* | |

*Estimate based on has_ccb flag in database

The numbers are sobering. Less than 2% of projects in the database carry CCP labels. CORSIA eligibility—required for aviation compliance—covers only 224 projects. Article 6 authorization, which involves host country approval under the Paris Agreement, is vanishingly rare at 33 projects.

This creates a supply-demand mismatch. Buyer demand is shifting toward quality-tier credits, but quality-tier supply remains a sliver of the market. The result is the price premium data shows: removal credits priced 381% above reduction credits, and rising. ---

IV. Case Studies in Scrutiny

Visibility invites scrutiny. The buyers with the largest public footprints face the most intense examination of their carbon credit claims.

Shell: Volume Leader, Litigation Target

Shell has retired 37.7 million credits since 2018—more than any other corporate buyer in the VCM.fyi database. The portfolio is heavily weighted toward Indonesian forest projects (top country) and averages 2017 vintage—meaning many credits are 7+ years old.

Yet Shell faces ongoing legal pressure in the Netherlands over its climate strategy, including the role of offsets. The Dutch court's 2021 ruling requiring Shell to cut emissions 45% by 2030 specifically questioned reliance on offsets. Shell's appeal is ongoing, and the company has scaled back its "carbon neutral" product claims in some markets.

The Shell case illustrates the paradox facing large buyers: significant investment in carbon credits has not insulated the company from legal or reputational challenge. If anything, the scale of purchasing has invited more scrutiny, not less.

Delta Air Lines: The Quiet Exit

Delta's trajectory tells a different story. Between 2015 and 2022, the airline retired 11 million credits, branded itself "the world's first carbon-neutral airline," and invested heavily in marketing the claim.

Then came the lawsuit. In May 2023, a class action accused Delta of greenwashing, alleging its carbon neutrality claims were misleading because the offsets it purchased—primarily renewable energy credits from China and India—did not represent real emissions reductions.

Delta hasn't retired a single credit since April 2022. The company's carbon neutral claims have disappeared from marketing materials. Delta's 11 million credits, averaging 2014 vintage and heavily concentrated in now-discredited project types, represent exactly the portfolio exposure that today's buyers seek to avoid.

The Pattern

Both cases share common elements: high-visibility companies, large offset volumes, portfolios concentrated in project types now considered low-quality or high-scrutiny, and eventual legal or reputational challenge. The lesson is not that carbon credits don't work. It's that credit quality and claim framing matter enormously—and that yesterday's acceptable portfolio may be tomorrow's litigation exposure.

V. The Regulatory Trajectory

The regulatory environment for carbon credit claims has tightened considerably since 2023. Corporate legal and sustainability teams are navigating a shifting landscape.

EU Empowering Consumers Directive

The EU's Empowering Consumers for the Green Transition Directive, which entered into force in 2024, restricts environmental claims including carbon neutrality assertions. Under the directive:

Claims of carbon neutrality based solely on offsets are presumptively misleading
Companies must demonstrate emissions reductions before relying on offsets
Third-party verification of claims becomes standard
Penalties for greenwashing can reach 4% of annual turnover

ICVCM Core Carbon Principles

The Integrity Council's CCP framework establishes threshold quality requirements for carbon credits. To date, the ICVCM has approved methodologies covering approximately 51 million credits in circulation, though only a fraction carry the CCP label in practice.

The market increasingly treats CCP certification as a floor for acceptable credit quality. Buyers seeking reputational protection are gravitating toward CCP-labeled supply, creating the price premium the data shows. ---

VI. Portfolio Implications

The patterns in the data suggest several risk dimensions corporate buyers should consider.

Credit Type Risk Matrix

Vintage Risk

Older vintages face increasing scrutiny. Credits from 2014-2016—common in portfolios of buyers who made early "carbon neutral" commitments—are now 9-11 years old. This raises questions:

Were baseline assumptions accurate over such periods?
Do monitoring reports exist for all years?
Has the project's additionality been maintained?

Delta's portfolio averaged 2014 vintage. Shell's averages 2017. The age of credits in a portfolio is itself a risk factor. ---

The Bottom Line

The voluntary carbon market in late 2025 is neither dead nor dying. Retirement activity continues at pace. Thousands of buyers remain active. New entrants are joining, particularly in aviation ahead of CORSIA compliance.

But the market is bifurcating—and rapidly. A quality tier is emerging around CCP labels, CORSIA eligibility, and Article 6 authorization. Price premiums for this tier are substantial and rising. Credits outside the quality tier face declining demand and increasing reputational risk.

For corporate buyers, the strategic question is straightforward even if the execution is complex: does your portfolio sit on the right side of this divide?

The data suggests that doing nothing is itself a choice—and increasingly, a risky one. ---

Data sources: VCM.fyi registry database (11,093 projects, 464,707 retirement transactions tracked), Ecosystem Marketplace State of the VCM 2025, Sylvera Q3 2025 Carbon Data Snapshot, ICVCM methodology approvals, public company disclosures and litigation filings.

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