After nearly a decade of consolidation, the voluntary carbon market (VCM) entered its mainstreaming phase around 2017. With the Paris Agreement in effect, the Sustainable Development Goals (SDGs) gaining traction, and increasing participation from both the private and public sectors, the VCM evolved from being a peripheral corporate responsibility tool into a critical pillar supporting the global net-zero transition.
During this phase, the market expanded rapidly in scale, attracted a broader mix of participants, and saw continuous innovation in standards and credit types. Yet, rapid growth also brought scrutiny. Concerns over credit quality and transparency emerged, prompting the development of stronger governance mechanisms. Notably, high-integrity credits began to gain recognition in compliance systems across some countries, signaling that the VCM was no longer just voluntary—it was starting to align with national policies and regulatory frameworks.
Diversifying Participants and Deepening Climate Responsibility
Since 2017, the VCM has drawn in companies far beyond traditional heavy emitters. Businesses across industries—technology, finance, fashion, retail, and more—integrated carbon credits into their broader climate strategies. The shift was not merely about offsetting residual emissions but about embedding offsets as part of a larger net-zero pathway.
The Science Based Targets initiative (SBTi) exemplifies this trend. It enables companies to set emission-reduction goals grounded in climate science, aligned with the Paris Agreement’s 1.5°C ambition. As of mid-2025, more than 10,000 companies had joined the initiative, with over 8,000 already committed to science-based targets. This evolution—from earlier “carbon neutrality” claims to formal net-zero commitments—illustrates how corporate climate responsibility has deepened, reinforcing the role of the VCM in mainstream business practice.
Evolving Standards and the Quality Debate
On the standards side, both refinements and innovations reshaped the market. Established systems such as Verra’s VCS and the Gold Standard strengthened their methodologies and transparency requirements, while new entrants like Puro.earth created pathways for emerging technological removals. Approaches such as direct air capture and biochar gained momentum, attracting buyers like Microsoft and Google, who saw both compliance value and long-term innovation potential in supporting these early-stage solutions.
The market reached its financial peak in 2021, with trading volumes valued at around USD 2 billion. However, this momentum was short-lived. Media investigations and academic studies questioned the integrity of certain projects—particularly REDD initiatives—suggesting that carbon reductions were overstated or inconsistently measured. These doubts triggered a crisis of confidence, leading to a sharp 56% drop in market value between 2022 and 2023.
Instead of collapsing, the market responded with reforms. Verra and other standards tightened eligibility rules, invalidated non-compliant projects, and revoked approvals for underperforming verification bodies. At the same time, new governance structures emerged. The Integrity Council for the Voluntary Carbon Market (ICVCM) established benchmarks for high-quality credits, while the Voluntary Carbon Market Integrity Initiative (VCMI) focused on guiding companies in responsible credit use. Together, these initiatives directly addressed transparency concerns, rebuilding trust and supporting a healthier market ecosystem.
In the voluntary carbon market, trust is the foundation. Buyers must be confident that carbon credits represent real, verifiable reductions; without this assurance, investment slows and demand weakens. Governance reforms and oversight were therefore not just corrective measures, but critical steps in safeguarding the VCM’s long-term viability.
Linking Voluntary and Compliance Systems
In recent years, some governments—including Costa Rica and South Africa—have started to recognize certain VCM credits for use in tax reductions or legal compliance. This integration underscores the VCM’s growing legitimacy and signals a possible convergence between voluntary and compliance markets in the future. Such recognition expands the application of voluntary credits and positions the VCM as a bridge in global carbon governance.
Looking Back—and Ahead
Over the past thirty years, the voluntary carbon market has evolved from a small experimental initiative into a central part of global climate action. Its development highlights the changing role of businesses, the integration of sustainability into corporate decision-making, and the dynamic interaction between international policy and private-sector innovation.
The road ahead is not without challenges, as questions of quality, equity, and credibility remain. Yet it is through decades of experimentation, reform, and adaptation that the voluntary carbon market has grown stronger, more resilient, and better equipped to help the world tackle the climate crisis.
Reference ： SBTi . Puro.earth . Carbon Offset Guide . Verra VVB . CarbonCredits.com . ICVCM . VCMI